Animator refactoring & fixes

Tweaks animators to have less unnecessary refcounting

 Pull animator management out into seperate class

 More control to tweak animator lifecycle, such as doing
 Java-side handling of start delay by attaching but not
 starting the animator

Change-Id: I4ff8207580ca11fb38f45ef0007b406e0097281c

libs/hwui/renderthread/DrawFrameTask.cpp

@@ -127,7 +127,7 @@ bool DrawFrameTask::syncFrameState(TreeInfo& info) {
     Caches::getInstance().textureCache.resetMarkInUse();
 
     for (size_t i = 0; i < mLayers.size(); i++) {
-        mContext->processLayerUpdate(mLayers[i].get(), info);
+        mContext->processLayerUpdate(mLayers[i].get());
     }
     mLayers.clear();
     mContext->prepareTree(info);