android: Remove providers from ProGuard configuration

We are no longer using resources to load providers on Android. Instead,
we are calling Class.forName() for known providers. ProGuard is able to
detect these usages automatically.

Author: ejona86

android-interop-testing/app/proguard-rules.pro

@@ -14,13 +14,3 @@
 -dontwarn org.mockito.**
 -dontwarn sun.reflect.**
 -dontwarn android.test.**
-
-# Providers use their name to load files from META-INF
--keepnames class io.grpc.ServerProvider
--keepnames class io.grpc.ManagedChannelProvider
--keepnames class io.grpc.NameResolverProvider
-
-# The Provider implementations must be kept and retain their names, since the
-# names are referenced from META-INF
--keep class io.grpc.internal.DnsNameResolverProvider
--keep class io.grpc.okhttp.OkHttpChannelProvider

examples/android/app/proguard-rules.pro

@@ -12,13 +12,3 @@
 -dontwarn sun.misc.Unsafe
 -dontwarn com.google.common.**
 -dontwarn okio.**
-
-# Providers use their name to load files from META-INF
--keepnames class io.grpc.ServerProvider
--keepnames class io.grpc.ManagedChannelProvider
--keepnames class io.grpc.NameResolverProvider
-
-# The Provider implementations must be kept and retain their names, since the
-# names are referenced from META-INF
--keep class io.grpc.internal.DnsNameResolverProvider
--keep class io.grpc.okhttp.OkHttpChannelProvider