Add -implicit:class to several test methods in ExtensionTest to work …

…around a compiler warning that causes test failures. See discussion in #407.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=141184041

value/src/test/java/com/google/auto/value/processor/ExtensionTest.java

@@ -166,7 +166,7 @@ public void testDoesntRaiseWarningForConsumedProperties() {
         "  }",
         "}");
     assertThat(impl)
-        .withCompilerOptions("-Xlint:-processing")
+        .withCompilerOptions("-Xlint:-processing", "-implicit:class")
         .processedWith(new AutoValueProcessor(ImmutableList.of(new FooExtension())))
         .compilesWithoutWarnings();
   }
@@ -187,7 +187,7 @@ public void testDoesntRaiseWarningForToBuilder() {
         "  }",
         "}");
     assertThat(impl)
-        .withCompilerOptions("-Xlint:-processing")
+        .withCompilerOptions("-Xlint:-processing", "-implicit:class")
         .processedWith(new AutoValueProcessor(ImmutableList.of(new FooExtension())))
         .compilesWithoutWarnings();
   }
@@ -332,7 +332,7 @@ public void testConsumeMethodWithArguments() throws Exception {
         "  abstract void writeToParcel(Object parcel, int flags);",
         "}");
     assertThat(javaFileObject)
-        .withCompilerOptions("-Xlint:-processing")
+        .withCompilerOptions("-Xlint:-processing", "-implicit:class")
         .processedWith(
             new AutoValueProcessor(ImmutableList.of(new FakeWriteToParcelExtension())))
         .compilesWithoutWarnings();
@@ -504,7 +504,7 @@ private void doTestBadJarDoesntBlowUp(File badJar) throws IOException {
         "public abstract class Baz {",
         "}");
     SuccessfulCompilationClause success = assertThat(javaFileObject)
-        .withCompilerOptions("-Xlint:-processing")
+        .withCompilerOptions("-Xlint:-processing", "-implicit:class")
         .processedWith(new AutoValueProcessor(badJarLoader))
         .compilesWithoutError();
     success.withWarningContaining(