Removed keeps for unused member variables.

chrome/android/java/proguard.flags

 # Keep line number information, useful for stack traces.
 -keepattributes SourceFile,LineNumberTable
 
 # Keep the annotations.
 -keep @interface ***
 
 # Disable obfuscation for the following two packages.
 -keepnames class com.google.android.apps.chrome.**,org.chromium.** {
   *;
 }
 
-# Keep all the primitive and String constants for for the following two packages.
--keepclassmembers class com.google.android.apps.chrome.**,org.chromium.** {
-  !private static final % *;
-  !private static final java.lang.String *;
-}
-
 # Fragments are loaded using reflection via Fragment.instantiate(Context,String)
 # This can be improved upon - see crbug.com/622023.
 -keep public class com.google.android.apps.chrome** extends android.app.Fragment
 -keep public class org.chromium** extends android.app.Fragment
 
 # Keeps for class level annotations.
 -keep @**.UsedByReflection class *
 -keep @**.VisibleForTesting class *
 
 # Keeps for method level annotations.
@@ skipping 195 matching lines @@
 # Needed for chrome_sync_shell_test_apk. Note - these do no affect chrome_apk's
 # size.
 -keep class org.chromium.sync.protocol.* { *; }
 
 # These resources are referenced in tests, but not in the real application.
 -keepclassmembers class org.chromium.chrome.R$id {
   int webapp_splash_space;
   int mr_chooser_list;
   int find_toolbar;
 }