Revert StringUtils.trim and update expected R8 version.

Bug: b/229695990
Change-Id: I6d9fcc52d80388cad637d34179cc6414ac7ef8e9
diff --git a/src/main/java/com/android/tools/r8/utils/StringUtils.java b/src/main/java/com/android/tools/r8/utils/StringUtils.java
index 84dd752..f1e4e18 100644
--- a/src/main/java/com/android/tools/r8/utils/StringUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/StringUtils.java
@@ -320,7 +320,19 @@
   }
 
   public static String trim(String s) {
-    return stripLeadingBOM(s).strip();
+    int beginIndex = 0;
+    int endIndex = s.length();
+    while (beginIndex < endIndex && isWhitespace(s.charAt(beginIndex))) {
+      beginIndex++;
+    }
+    while (endIndex - 1 > beginIndex && isWhitespace(s.charAt(endIndex - 1))) {
+      endIndex--;
+    }
+    if (beginIndex > 0 || endIndex < s.length()) {
+      return s.substring(beginIndex, endIndex);
+    } else {
+      return s;
+    }
   }
 
   /** Returns true if {@param s} only contains the characters [0-9]. */
diff --git a/src/test/java/com/android/tools/r8/R8CfVersionTest.java b/src/test/java/com/android/tools/r8/R8CfVersionTest.java
index fcc29c1..d7ab6c8 100644
--- a/src/test/java/com/android/tools/r8/R8CfVersionTest.java
+++ b/src/test/java/com/android/tools/r8/R8CfVersionTest.java
@@ -18,7 +18,7 @@
 @RunWith(Parameterized.class)
 public class R8CfVersionTest extends TestBase {
 
-  private final CfVersion targetVersion = CfVersion.V1_8;
+  private final CfVersion targetVersion = CfVersion.V11;
 
   @Parameters(name = "{0}")
   public static TestParametersCollection data() {
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/WhyAreYouKeepingAllTest.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/WhyAreYouKeepingAllTest.java
index 94bdbf1..915d92b 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/WhyAreYouKeepingAllTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/WhyAreYouKeepingAllTest.java
@@ -6,6 +6,7 @@
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.not;
 
+import com.android.tools.r8.JdkClassFileProvider;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
@@ -45,6 +46,7 @@
   public void test() throws Throwable {
     testForR8(Backend.CF)
         .addProgramFiles(ToolHelper.R8_WITH_RELOCATED_DEPS_JAR)
+        .addLibraryProvider(JdkClassFileProvider.fromSystemJdk())
         .addKeepRuleFiles(MAIN_KEEP)
         .addKeepRules(WHY_ARE_YOU_KEEPING_ALL)
         .collectStdout()
diff --git a/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java b/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java
index 8279af3..acadcc6 100644
--- a/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java
+++ b/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java
@@ -6,13 +6,29 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
 
+import com.android.tools.r8.TestBase;
+import com.android.tools.r8.TestParameters;
+import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
 
-public class StringUtilsTest {
+@RunWith(Parameterized.class)
+public class StringUtilsTest extends TestBase {
+
+  @Parameters(name = "{0}")
+  public static TestParametersCollection data() {
+    return getTestParameters().withNoneRuntime().build();
+  }
+
+  public StringUtilsTest(TestParameters parameters) {
+    parameters.assertNoneRuntime();
+  }
 
   @Test
   public void splitLines() {