add functionality to enable/disable clicks on a MultiToggleImageButton
without affecting its visual state.

bug: 17014507
Change-Id: I824e07d518cce9768cf48f4c50afe079ebff4121
diff --git a/src/com/android/camera/PhotoModule.java b/src/com/android/camera/PhotoModule.java
index 59539b0..2268f00 100644
--- a/src/com/android/camera/PhotoModule.java
+++ b/src/com/android/camera/PhotoModule.java
@@ -388,13 +388,16 @@
             // in the new module.  The new module will set the enabled/disabled
             // of this button when the module's preferred camera becomes available.
             ButtonManager buttonManager = mActivity.getButtonManager();
-            buttonManager.disableButton(ButtonManager.BUTTON_HDR_PLUS);
+
+            buttonManager.disableButtonClick(ButtonManager.BUTTON_HDR_PLUS);
 
             mAppController.getCameraAppUI().freezeScreenUntilPreviewReady();
 
             // Do not post this to avoid this module switch getting interleaved with
             // other button callbacks.
             mActivity.onModeSelected(mGcamModeIndex);
+
+            buttonManager.enableButtonClick(ButtonManager.BUTTON_HDR_PLUS);
         }
     }