Bug 1262273 - Keep appcompat-v7 from getting Proguarded out. r=mcomella

See https://code.google.com/p/android/issues/detail?id=78293.

MozReview-Commit-ID: HNcSaCEBlwX

--HG--
extra : rebase_source : 06fba8b50cb328ec89dcaba14b484d27be252d66
extra : histedit_source : bae8cce48194be5b4b9d3958400d6d99c0fb5d5d

mobile/android/config/proguard/appcompat-v7-keeps.cfg

@@ -0,0 +1,11 @@
+# Avoid https://code.google.com/p/android/issues/detail?id=187611 and
+# http://stackoverflow.com/q/32813894 when building with Gradle.  Why
+# these aren't defined in appcompat-v7.aar/proguard.txt is beyond me.
+
+-keep public class android.support.v7.widget.** { *; }
+-keep public class android.support.v7.internal.widget.** { *; }
+-keep public class android.support.v7.internal.view.menu.** { *; }
+
+-keep public class * extends android.support.v4.view.ActionProvider {
+    public <init>(android.content.Context);
+}

mobile/android/config/proguard/proguard.cfg

@@ -250,3 +250,4 @@
 
 -include "leakcanary-keeps.cfg"
 
+-include "appcompat-v7-keeps.cfg"