rename GrDrawTargetCaps.h to GrCaps.h and move to include

Review URL: https://codereview.chromium.org/1135113005
diff --git a/src/gpu/GrDrawTarget.cpp b/src/gpu/GrDrawTarget.cpp
index 35a19e4..20288a9 100644
--- a/src/gpu/GrDrawTarget.cpp
+++ b/src/gpu/GrDrawTarget.cpp
@@ -9,8 +9,8 @@
 #include "GrDrawTarget.h"
 
 #include "GrBatch.h"
+#include "GrCaps.h"
 #include "GrContext.h"
-#include "GrDrawTargetCaps.h"
 #include "GrPath.h"
 #include "GrPipeline.h"
 #include "GrMemoryPool.h"