Clean up physical coupling

Narrow the use of #include directives in hwui, replacing with forward
declarations where straightforward. Speeds compiles; doesn't do any
restructuring of code.

Change-Id: Icac2baffb5896f55d8c6718e9bd9d4bfa02d3ca0
diff --git a/libs/hwui/TessellationCache.h b/libs/hwui/TessellationCache.h
index 688a699..a7c50eb 100644
--- a/libs/hwui/TessellationCache.h
+++ b/libs/hwui/TessellationCache.h
@@ -24,7 +24,6 @@
 #include "Debug.h"
 #include "utils/Macros.h"
 #include "utils/Pair.h"
-#include "VertexBuffer.h"
 
 class SkBitmap;
 class SkCanvas;
@@ -36,6 +35,7 @@
 namespace uirenderer {
 
 class Caches;
+class VertexBuffer;
 
 ///////////////////////////////////////////////////////////////////////////////
 // Classes