Use fragment context in AppHeaderController

The application context doesn't have the correct theme, use
fragment context instead

Fix: 36489386
Fix: 36516826
Test: RunSettingsRoboTests & Screenshot
Change-Id: I8285584220796264d85ea570df5b1df6ebeb275f

src/com/android/settings/applications/AppHeaderController.java

@@ -90,7 +90,7 @@ public class AppHeaderController {
         if (appHeader != null) {
             mAppHeader = appHeader;
         } else {
-            mAppHeader = LayoutInflater.from(mContext)
+            mAppHeader = LayoutInflater.from(fragment.getContext())
                     .inflate(R.layout.app_details, null /* root */);
         }
     }