Use kotlinc 1.9.21 as max supported and 1.7 as min-supported

This will move kotlinc 1.6 to our old bot testing.

Fixes: b/315458778
Change-Id: Ice19284f4c254bc1eba49b2fc437bf6ac866258c
diff --git a/src/test/java/com/android/tools/r8/KotlinCompilerTool.java b/src/test/java/com/android/tools/r8/KotlinCompilerTool.java
index a0821d2..1075fd9 100644
--- a/src/test/java/com/android/tools/r8/KotlinCompilerTool.java
+++ b/src/test/java/com/android/tools/r8/KotlinCompilerTool.java
@@ -74,10 +74,11 @@
     KOTLINC_1_6_0("kotlin-compiler-1.6.0"),
     KOTLINC_1_7_0("kotlin-compiler-1.7.0"),
     KOTLINC_1_8_0("kotlin-compiler-1.8.0"),
+    KOTLINC_1_9_21("kotlin-compiler-1.9.21"),
     KOTLIN_DEV("kotlin-compiler-dev");
 
-    public static final KotlinCompilerVersion MIN_SUPPORTED_VERSION = KOTLINC_1_6_0;
-    public static final KotlinCompilerVersion MAX_SUPPORTED_VERSION = KOTLINC_1_8_0;
+    public static final KotlinCompilerVersion MIN_SUPPORTED_VERSION = KOTLINC_1_7_0;
+    public static final KotlinCompilerVersion MAX_SUPPORTED_VERSION = KOTLINC_1_9_21;
 
     private final String folder;
 
diff --git a/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java b/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java
index 9b536f6..955048d 100644
--- a/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java
@@ -6,6 +6,7 @@
 
 import static com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion.KOTLINC_1_3_72;
 import static com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion.KOTLINC_1_8_0;
+import static com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion.KOTLINC_1_9_21;
 
 import com.android.tools.r8.DexIndexedConsumer.ArchiveConsumer;
 import com.android.tools.r8.KotlinTestBase;
@@ -108,9 +109,11 @@
         .assertNoErrorMessages()
         // -keepattributes Signature is added in kotlin-reflect from version 1.4.20.
         .applyIf(kotlinParameters.is(KOTLINC_1_3_72), TestCompileResult::assertNoInfoMessages)
-        // TODO(b/269794485): Figure out why generic signatures fail using kotlin-dev.
+        // TODO(b/269794485): Figure out why generic signatures fail using 1.9.
         .applyIf(
-            kotlinParameters.getCompiler().isNot(KOTLINC_1_3_72) && !kotlinParameters.isKotlinDev(),
+            kotlinParameters.getCompiler().isNot(KOTLINC_1_3_72)
+                && kotlinParameters.getCompiler().isNot(KOTLINC_1_9_21)
+                && !kotlinParameters.isKotlinDev(),
             TestBase::verifyAllInfoFromGenericSignatureTypeParameterValidation)
         .apply(KotlinMetadataTestBase::verifyExpectedWarningsFromKotlinReflectAndStdLib)
         .writeToZip(foo.toPath())