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/renderthread/EglManager.cpp b/libs/hwui/renderthread/EglManager.cpp
index a87834e..dd6211b 100644
--- a/libs/hwui/renderthread/EglManager.cpp
+++ b/libs/hwui/renderthread/EglManager.cpp
@@ -19,6 +19,7 @@
 #include <cutils/log.h>
 #include <cutils/properties.h>
 
+#include "../Caches.h"
 #include "../RenderState.h"
 #include "RenderThread.h"