Log source with visibility change

- Add a method in VisibilityLoggerMixin to log visible event using
  LogMaker, which allows logging additional FIELD_CONTEXT field.
- In Utils.startFragment, add current page's metricsCategory as an extra
  to next page.
- In next page's onResume(), extract the previous page's metricsCategory
  and send it to VisibilityLoggerMixin.visible()
- Update all caller with additional paramters

Change-Id: I8e1f2597fa465b7d3aa16fa1d21c052a3219694a
Fix: 35359289
Test: RunSettingsRoboTests

src/com/android/settings/dashboard/DashboardSummary.java

@@ -134,9 +134,11 @@ public class DashboardSummary extends InstrumentedFragment
 
         ((SettingsDrawerActivity) getActivity()).addCategoryListener(this);
         mSummaryLoader.setListening(true);
+        final int metricsCategory = getMetricsCategory();
         for (Condition c : mConditionManager.getConditions()) {
             if (c.shouldShow()) {
-                mMetricsFeatureProvider.visible(getContext(), c.getMetricsConstant());
+                mMetricsFeatureProvider.visible(getContext(), metricsCategory,
+                        c.getMetricsConstant());
             }
         }
         if (DEBUG_TIMING) {