Retract GrTexture*.h & GrRenderTarget*.h from other headers

This does push some additional work (& includes) into the .cpp files.

Change-Id: I27c847e371802270d13594dcc22aae44039990bb
Reviewed-on: https://skia-review.googlesource.com/19660
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/tests/ResourceCacheTest.cpp b/tests/ResourceCacheTest.cpp
index 460d4ee..2429fbd 100644
--- a/tests/ResourceCacheTest.cpp
+++ b/tests/ResourceCacheTest.cpp
@@ -16,11 +16,11 @@
 #include "GrGpu.h"
 #include "GrGpuResourceCacheAccess.h"
 #include "GrGpuResourcePriv.h"
-#include "GrRenderTarget.h"
-#include "GrRenderTargetPriv.h"
 #include "GrResourceCache.h"
 #include "GrResourceProvider.h"
 #include "GrTest.h"
+#include "GrTexture.h"
+
 #include "SkCanvas.h"
 #include "SkGr.h"
 #include "SkMessageBus.h"