Remove unused code from HWUI Layer

Change-Id: If9046add5ca5a647351187c5809841edcf0bfa9b

libs/hwui/Layer.cpp

@@ -54,8 +54,6 @@ Layer::~Layer() {
     if (texture.mId) {
         texture.deleteTexture();
     }
-
-    delete[] mesh;
 }
 
 void Layer::onGlContextLost() {

libs/hwui/Layer.h

@@ -188,12 +188,6 @@ public:
      */
     Rect clipRect;
 
-    /**
-     * If the layer can be rendered as a mesh, this is non-null.
-     */
-    TextureVertex* mesh = nullptr;
-    GLsizei meshElementCount = 0;
-
 private:
     Caches& caches;