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/PatchCache.h b/libs/hwui/PatchCache.h
index 9f2c9a5..1e40997 100644
--- a/libs/hwui/PatchCache.h
+++ b/libs/hwui/PatchCache.h
@@ -25,12 +25,13 @@
 
 #include "AssetAtlas.h"
 #include "Debug.h"
-#include "Patch.h"
 #include "utils/Pair.h"
 
 namespace android {
 namespace uirenderer {
 
+class Patch;
+
 ///////////////////////////////////////////////////////////////////////////////
 // Defines
 ///////////////////////////////////////////////////////////////////////////////