Fix proguard template to avoid shrinking XML-only references

See 16384: ProGuard template generated by the ADT is flawed

Change-Id: I6ebbcf059bbee8c485747dcee55f4ecfa14b6831
diff --git a/files/proguard.cfg b/files/proguard.cfg
index 12dd039..b1cdf17 100644
--- a/files/proguard.cfg
+++ b/files/proguard.cfg
@@ -18,14 +18,18 @@
     native <methods>;
 }
 
--keepclasseswithmembernames class * {
+-keepclasseswithmembers class * {
     public <init>(android.content.Context, android.util.AttributeSet);
 }
 
--keepclasseswithmembernames class * {
+-keepclasseswithmembers class * {
     public <init>(android.content.Context, android.util.AttributeSet, int);
 }
 
+-keepclassmembers class * extends android.app.Activity {
+   public void *(android.view.View);
+}
+
 -keepclassmembers enum * {
     public static **[] values();
     public static ** valueOf(java.lang.String);