Don't add API annotations in the internal R.java

I'm trying to enable a check for the following structure:
```
/** @hide */
public class Class1 {
    /** @hide */
    @SystemApi // Invalid because the class is hidden.
    public void method1() { }
}
```

The internal R.java file violates this, which this change is going to fix.

Bug: 159162473
Test: build (treehugger)
Test: atest aapt2_tests

Change-Id: I613e8611ddaf5f8e4761d351d4cd0142d59c7cc9

1 files changed, 15 insertions, 0 deletions

diff --git a/tools/aapt2/java/AnnotationProcessor_test.cpp b/tools/aapt2/java/AnnotationProcessor_test.cpp
index 7d0a4e9af632..6bc8902a6dcf 100644
--- a/tools/aapt2/java/AnnotationProcessor_test.cpp
+++ b/tools/aapt2/java/AnnotationProcessor_test.cpp
@@ -91,6 +91,21 @@ TEST(AnnotationProcessorTest, EmitsTestApiAnnotationAndRemovesFromComment) {
   EXPECT_THAT(annotations, HasSubstr("This is a test API"));
 }
 
+TEST(AnnotationProcessorTest, NotEmitSystemApiAnnotation) {
+  AnnotationProcessor processor;
+  processor.AppendComment("@SystemApi This is a system API");
+
+  std::string annotations;
+  StringOutputStream out(&annotations);
+  Printer printer(&out);
+  processor.Print(&printer, true /* strip_api_annotations */);
+  out.Flush();
+
+  EXPECT_THAT(annotations, Not(HasSubstr("@android.annotation.SystemApi")));
+  EXPECT_THAT(annotations, Not(HasSubstr("@SystemApi")));
+  EXPECT_THAT(annotations, HasSubstr("This is a system API"));
+}
+
 TEST(AnnotationProcessor, ExtractsFirstSentence) {
   EXPECT_THAT(AnnotationProcessor::ExtractFirstSentence("This is the only sentence"),
               Eq("This is the only sentence"));