Bug 824132: Persona sends a Reset message on start. [r=mfinkle]

--HG--
extra : rebase_source : e8e47801fbc3f4ec55e6d7637e4586a587cdda16

mobile/android/base/LightweightTheme.java

@@ -113,18 +113,20 @@ public class LightweightTheme implements GeckoEventListener {
     }
 
     public void resetLightweightTheme() {
-        // Reset the bitmap.
+        if (mBitmap != null) {
-        mBitmap = null;
+            // Reset the bitmap.
+            mBitmap = null;
 
-        // Post the reset on the UI thread.
+            // Post the reset on the UI thread.
-        for (OnChangeListener listener : mListeners) {
+            for (OnChangeListener listener : mListeners) {
-             final OnChangeListener oneListener = listener;
+                 final OnChangeListener oneListener = listener;
-             oneListener.post(new Runnable() {
+                 oneListener.post(new Runnable() {
-                 @Override
+                     @Override
-                 public void run() {
+                     public void run() {
-                     oneListener.onLightweightThemeReset();
+                         oneListener.onLightweightThemeReset();
-                 }
+                     }
-             });
+                 });
+            }
         }
     }
 
@@ -162,6 +164,21 @@ public class LightweightTheme implements GeckoEventListener {
         }
     }
 
+
+    /**
+     * A lightweight theme is enabled only if there is an active bitmap.
+     *
+     * @return True if the theme is enabled.
+     */
+    public boolean isEnabled() {
+        return (mBitmap != null);
+    }
+
+    /**
+     * Based on the luminance of the domanint color, a theme is classified as light or dark.
+     *
+     * @return True if the theme is light.
+     */
     public boolean isLightTheme() {
         return mIsLight;
     }