binder: compile warnings; RequiresPermission missing, readParcelable(ClassLoader) deprecated

[ejona86]

The following warnings prevent building grpc-binder with -PfailOnWarnings=true, which sets -Werror. class file for android.annotation.RequiresPermission not found in particular is pretty nasty as it isn't clear what is going on and you can't silence the single warning.

> Task :grpc-binder:compileDebugUnitTestJavaWithJavac
grpc-java/binder/src/test/java/io/grpc/binder/internal/ParcelableInputStreamTest.java:91: warning: [deprecation] <T>readParcelable(ClassLoader) in Parcel has been deprecated
    assertThat((TestParcelable) parcel.readParcelable(getClass().getClassLoader()))
                                      ^
  where T is a type-variable:
    T extends Parcelable declared in method <T>readParcelable(ClassLoader)
grpc-java/binder/src/test/java/io/grpc/binder/internal/ParcelableInputStreamTest.java:116: warning: [deprecation] <T>readParcelable(ClassLoader) in Parcel has been deprecated
    assertThat((TestParcelable) parcel.readParcelable(getClass().getClassLoader()))
                                      ^
  where T is a type-variable:
    T extends Parcelable declared in method <T>readParcelable(ClassLoader)
~/.gradle/caches/modules-2/files-2.1/org.robolectric/shadows-framework/4.9.2/8854520515f61e7f8319534dbbea3071cd282c54/shadows-framework-4.9.2.jar(/org/robolectric/shadows/ShadowDevicePolicyManager.class): warning: Cannot find annotation method 'value()' in type 'RequiresPermission': class file for android.annotation.RequiresPermission not found
~/.gradle/caches/modules-2/files-2.1/org.robolectric/shadows-framework/4.9.2/8854520515f61e7f8319534dbbea3071cd282c54/shadows-framework-4.9.2.jar(/org/robolectric/shadows/ShadowDevicePolicyManager.class): warning: Cannot find annotation method 'value()' in type 'RequiresPermission'
~/.gradle/caches/modules-2/files-2.1/org.robolectric/shadows-framework/4.9.2/8854520515f61e7f8319534dbbea3071cd282c54/shadows-framework-4.9.2.jar(/org/robolectric/shadows/ShadowDevicePolicyManager.class): warning: Cannot find annotation method 'value()' in type 'RequiresPermission'
~/clients/grpc-java/binder/src/test/java/io/grpc/binder/SecurityPoliciesTest.java:532: warning: [deprecation] signatures in PackageInfo has been deprecated
        packageInfo.signatures = this.signatures;
                   ^
6 warnings

CC @markb74, @jdcormie

[markb74]

We'll need to suppress the both the readParcelable and signatures warnings.

The new readParcelable method doesn't exist before Android 13, and the signatures code is testing support for older Android versions.

The RequiresPermission one seems to be an issue in robolectric?

[ejona86]

Yeah, I agree, but at the very least we can add @SuppressWarnings("deprecations") with a comment to the code. I would have done that in #10299 (where this came up), but that RequiresPermission thing was super strange.

It does seem an issue with Robolectric, but I'm also not clear on why Robolectric would be using the private versions of those annotations. I did try upgrading to the newest Robolectric and the issue was still present.

[jdcormie]

I found https://github.com/robolectric/robolectric/blob/master/ARCHITECTURE.md#android-framework-jars-and-instrumentation, which explains why robolectric shadows are able to depend on non-SDK Android classes marked @hide, such as android.annotation.RequiresPermission. I found that I can make the warnings go away by adding:

testCompileOnly "org.robolectric:android-all-instrumented:14-robolectric-10818077-i5"

but I'm not sure if that's the right fix. Many other projects appear to do this.

[ejona86]

If a compile-only dep fixes it, that seems low risk and easy.