diff --git a/src/main/java/com/android/tools/r8/androidapi/AndroidApiReferenceLevelCache.java b/src/main/java/com/android/tools/r8/androidapi/AndroidApiReferenceLevelCache.java
index df4cefd..9a4afa3 100644
--- a/src/main/java/com/android/tools/r8/androidapi/AndroidApiReferenceLevelCache.java
+++ b/src/main/java/com/android/tools/r8/androidapi/AndroidApiReferenceLevelCache.java
@@ -88,10 +88,12 @@
       // of the program.
       return appView.options().minApiLevel;
     }
-    return reference.apply(
-        androidApiLevelDatabase::getTypeApiLevel,
-        androidApiLevelDatabase::getFieldApiLevel,
-        androidApiLevelDatabase::getMethodApiLevel);
+    return reference
+        .apply(
+            androidApiLevelDatabase::getTypeApiLevel,
+            androidApiLevelDatabase::getFieldApiLevel,
+            androidApiLevelDatabase::getMethodApiLevel)
+        .max(appView.options().minApiLevel);
   }
 
   private boolean isReferenceToJavaLangObject(DexReference reference) {
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/DefaultInliningOracle.java b/src/main/java/com/android/tools/r8/ir/optimize/DefaultInliningOracle.java
index 0b7b139..8007b17 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/DefaultInliningOracle.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/DefaultInliningOracle.java
@@ -127,8 +127,7 @@
       WhyAreYouNotInliningReporter whyAreYouNotInliningReporter) {
     // Do not inline if the inlinee is greater than the api caller level.
     // TODO(b/188498051): We should not force inline lower api method calls.
-    if (reason != Reason.FORCE
-        && isApiSafeForInlining(method, singleTarget, appView.options()).isPossiblyFalse()) {
+    if (reason != Reason.FORCE && !isApiSafeForInlining(method, singleTarget, appView.options())) {
       whyAreYouNotInliningReporter.reportInlineeHigherApiCall();
       return false;
     }
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/classinliner/InlineCandidateProcessor.java b/src/main/java/com/android/tools/r8/ir/optimize/classinliner/InlineCandidateProcessor.java
index 5f05d8d..228c259 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/classinliner/InlineCandidateProcessor.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/classinliner/InlineCandidateProcessor.java
@@ -880,7 +880,7 @@
       return null;
     }
     // Check the api level is allowed to be inlined.
-    if (isApiSafeForInlining(method, singleTarget, appView.options()).isPossiblyFalse()) {
+    if (!isApiSafeForInlining(method, singleTarget, appView.options())) {
       return null;
     }
     // Check that the entire constructor chain can be inlined into the current context.
@@ -910,7 +910,7 @@
         return null;
       }
       // Check the api level is allowed to be inlined.
-      if (isApiSafeForInlining(method, encodedParent, appView.options()).isPossiblyFalse()) {
+      if (!isApiSafeForInlining(method, encodedParent, appView.options())) {
         return null;
       }
       parent =
diff --git a/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java b/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java
index 96c4a2b..73ee4de 100644
--- a/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java
@@ -8,18 +8,17 @@
 
 public class AndroidApiLevelUtils {
 
-  public static OptionalBool isApiSafeForInlining(
+  public static boolean isApiSafeForInlining(
       ProgramMethod caller, ProgramMethod inlinee, InternalOptions options) {
     if (!options.apiModelingOptions().enableApiCallerIdentification) {
-      return OptionalBool.TRUE;
+      return true;
     }
     if (caller.getHolderType() == inlinee.getHolderType()) {
-      return OptionalBool.TRUE;
+      return true;
     }
-    return OptionalBool.of(
-        caller
-            .getDefinition()
-            .getApiLevel()
-            .isGreaterThanOrEqualTo(inlinee.getDefinition().getApiLevelForCode()));
+    return caller
+        .getDefinition()
+        .getApiLevel()
+        .isGreaterThanOrEqualTo(inlinee.getDefinition().getApiLevelForCode());
   }
 }
diff --git a/src/main/java/com/android/tools/r8/utils/InternalOptions.java b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
index 0fdc11c..88c96ef 100644
--- a/src/main/java/com/android/tools/r8/utils/InternalOptions.java
+++ b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
@@ -1473,7 +1473,7 @@
     public Map<ClassReference, AndroidApiLevel> classApiMapping = new HashMap<>();
     public BiConsumer<MethodReference, AndroidApiLevel> tracedMethodApiLevelCallback = null;
 
-    public boolean enableApiCallerIdentification = false;
+    public boolean enableApiCallerIdentification = true;
     public boolean checkAllApiReferencesAreSet = true;
     public boolean useHashingDatabase = true;
 
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java
index 46ecc50..699bb50 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java
@@ -4,6 +4,7 @@
 package com.android.tools.r8.classmerging.vertical;
 
 import static com.android.tools.r8.smali.SmaliBuilder.buildCode;
+import static com.android.tools.r8.utils.AndroidApiLevel.K;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -315,10 +316,13 @@
           CF_DIR.resolve("FieldCollisionTest$A.class"),
           CF_DIR.resolve("FieldCollisionTest$B.class")
         };
-    Set<String> preservedClassNames =
-        ImmutableSet.of(
-            "classmerging.FieldCollisionTest",
-            "classmerging.FieldCollisionTest$B");
+    ImmutableSet.Builder<String> preservedNamesBuilder = ImmutableSet.builder();
+    preservedNamesBuilder.add("classmerging.FieldCollisionTest");
+    preservedNamesBuilder.add("classmerging.FieldCollisionTest$B");
+    if (parameters.isCfRuntime() || parameters.getApiLevel().isLessThan(K)) {
+      preservedNamesBuilder.add("classmerging.FieldCollisionTest$A");
+    }
+    Set<String> preservedClassNames = preservedNamesBuilder.build();
     runTest(
         testForR8(parameters.getBackend())
             .addKeepRules(getProguardConfig(EXAMPLE_KEEP))
diff --git a/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestAttributesUpdateTest.java b/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestAttributesUpdateTest.java
index 00575cd..bc389c9 100644
--- a/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestAttributesUpdateTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestAttributesUpdateTest.java
@@ -12,10 +12,12 @@
 import static junit.framework.TestCase.assertTrue;
 
 import com.android.tools.r8.Jdk9TestUtils;
+import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
+import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.graph.DexClass;
 import com.android.tools.r8.graph.NestMemberClassAttribute;
 import com.android.tools.r8.utils.StringUtils;
@@ -51,33 +53,72 @@
 
   @Test
   public void testClassMergingNestMemberRemoval() throws Exception {
-    testNestAttributesCorrect(MERGING_OUTER_CLASS, MERGING_OUTER_CLASS, MERGING_EXPECTED_RESULT, 3);
+    testNestAttributesCorrect(
+        MERGING_OUTER_CLASS,
+        MERGING_OUTER_CLASS,
+        MERGING_EXPECTED_RESULT,
+        3,
+        ThrowableConsumer.empty());
   }
 
   @Test
   public void testClassMergingNestHostRemoval() throws Exception {
     testNestAttributesCorrect(
-        MERGING_OUTER_CLASS + "$MiddleOuter", MERGING_OUTER_CLASS, MERGING_EXPECTED_RESULT, 2);
+        MERGING_OUTER_CLASS + "$MiddleOuter",
+        MERGING_OUTER_CLASS,
+        MERGING_EXPECTED_RESULT,
+        2,
+        builder -> {
+          builder.addOptionsModification(
+              internalOptions -> {
+                // The test makes an invoke to StringConcatFactory which is not known to DEX and
+                // we therefore fail to merge the classes.
+                internalOptions.apiModelingOptions().enableApiCallerIdentification = false;
+              });
+        });
   }
 
   @Test
   public void testTreePruningNestMemberRemoval() throws Exception {
-    testNestAttributesCorrect(PRUNING_OUTER_CLASS, PRUNING_OUTER_CLASS, PRUNING_EXPECTED_RESULT, 2);
+    testNestAttributesCorrect(
+        PRUNING_OUTER_CLASS,
+        PRUNING_OUTER_CLASS,
+        PRUNING_EXPECTED_RESULT,
+        2,
+        ThrowableConsumer.empty());
   }
 
   @Test
   public void testTreePruningNestHostRemoval() throws Exception {
     testNestAttributesCorrect(
-        PRUNING_OUTER_CLASS + "$Pruned", PRUNING_OUTER_CLASS, PRUNING_EXPECTED_RESULT, 1);
+        PRUNING_OUTER_CLASS + "$Pruned",
+        PRUNING_OUTER_CLASS,
+        PRUNING_EXPECTED_RESULT,
+        1,
+        ThrowableConsumer.empty());
   }
 
   public void testNestAttributesCorrect(
-      String mainClassName, String outerNestName, String expectedResult, int expectedNumClassesLeft)
+      String mainClassName,
+      String outerNestName,
+      String expectedResult,
+      int expectedNumClassesLeft,
+      ThrowableConsumer<R8FullTestBuilder> testBuilderConsumer)
       throws Exception {
     testNestAttributesCorrect(
-        mainClassName, outerNestName, expectedResult, true, expectedNumClassesLeft);
+        mainClassName,
+        outerNestName,
+        expectedResult,
+        true,
+        expectedNumClassesLeft,
+        testBuilderConsumer);
     testNestAttributesCorrect(
-        mainClassName, outerNestName, expectedResult, false, expectedNumClassesLeft);
+        mainClassName,
+        outerNestName,
+        expectedResult,
+        false,
+        expectedNumClassesLeft,
+        testBuilderConsumer);
   }
 
   public void testNestAttributesCorrect(
@@ -85,7 +126,8 @@
       String outerNestName,
       String expectedResult,
       boolean minification,
-      int expectedNumClassesLeft)
+      int expectedNumClassesLeft,
+      ThrowableConsumer<R8FullTestBuilder> testBuilderConsumer)
       throws Exception {
     String actualMainClassName = PACKAGE_NAME + mainClassName;
     testForR8(parameters.getBackend())
@@ -101,6 +143,7 @@
         .applyIf(parameters.isCfRuntime(), Jdk9TestUtils.addJdk9LibraryFiles(temp))
         .addKeepPackageNamesRule("nesthostexample")
         .addInliningAnnotations()
+        .apply(testBuilderConsumer)
         .compile()
         .inspect(
             inspector -> {
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ConstructorWithNonTrivialControlFlowTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ConstructorWithNonTrivialControlFlowTest.java
index 693b9bf..26bbf63 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ConstructorWithNonTrivialControlFlowTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ConstructorWithNonTrivialControlFlowTest.java
@@ -12,6 +12,7 @@
 import com.android.tools.r8.NeverPropagateValue;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
+import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.BooleanUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
@@ -56,9 +57,9 @@
 
   private void verifyClassInliningRemovesCandidate(CodeInspector inspector) {
     ClassSubject candidateClassSubject = inspector.clazz(Candidate.class);
-    if (enableClassInlining) {
-      // TODO(b/188388130): String.empty was added in AndroidApiLevel.G, so if this fails after
-      //  enabling api modeling then check for api level.
+    if (enableClassInlining
+        && (parameters.isDexRuntime()
+            && parameters.getApiLevel().isGreaterThanOrEqualTo(AndroidApiLevel.G))) {
       assertThat(candidateClassSubject, not(isPresent()));
     } else {
       assertThat(candidateClassSubject, isPresent());
diff --git a/tools/chrome_data.py b/tools/chrome_data.py
index 0d4329d..ebae542 100644
--- a/tools/chrome_data.py
+++ b/tools/chrome_data.py
@@ -248,6 +248,7 @@
         'inputs': [os.path.join(V180917_BASE, path) for path in INPUT_JARS],
         'pgconf': [os.path.join(V180917_BASE, path) for path in PG_CONFS],
         'libraries': [os.path.join(V180917_BASE, path) for path in LIBRARIES],
+        'min-api': '21',
     },
   },
   '200430': {