New layers API for Views.

This API can be used to back a view and its children with either a
software layer (bitmap) or hardware layer (FBO). Layers have
various usages, including color filtering and performance
improvements during animations.

Change-Id: Ifc3bea847918042730fc5a8c2d4206dd6c9420a3
diff --git a/libs/hwui/LayerCache.cpp b/libs/hwui/LayerCache.cpp
index 9ce0359..ec186a4 100644
--- a/libs/hwui/LayerCache.cpp
+++ b/libs/hwui/LayerCache.cpp
@@ -102,6 +102,7 @@
         layer->blend = true;
         layer->empty = true;
         layer->fbo = 0;
+        layer->colorFilter = NULL;
 
         glGenTextures(1, &layer->texture);
         glBindTexture(GL_TEXTURE_2D, layer->texture);