refactor parts of SkGr.cpp for use by SkImages

src/gpu/GrYUVProvider.h

Index: src/gpu/GrYUVProvider.h
diff --git a/src/gpu/GrYUVProvider.h b/src/gpu/GrYUVProvider.h
new file mode 100644
index 0000000000000000000000000000000000000000..e83ccbee474950c01aaee02c05121aacd28eb14b
--- /dev/null
+++ b/src/gpu/GrYUVProvider.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrYUVProvider_DEFINED
+#define GrYUVProvider_DEFINED
+
+#include "GrTypes.h"
+#include "SkImageInfo.h"
+
+class GrContext;
+class GrTexture;
+

[robertphillips, 2015/09/08 13:34:35]

// This exists b.c. ... 

?

[reed1, 2015/09/08 14:57:22]

Done.

+class GrYUVProvider {
+public:
+    virtual ~GrYUVProvider() {}
+
+    GrTexture* refAsTexture(GrContext*, const GrSurfaceDesc&, bool useCache);
+
+    virtual uint32_t onGetID() = 0;
+
+    enum {
+        kY_Index = 0,
+        kU_Index = 1,
+        kV_Index = 2,
+
+        kPlaneCount = 3
+    };
+

[robertphillips, 2015/09/08 13:34:35]

// returns false when ... ?

[reed1, 2015/09/08 14:57:22]

Done.

+    virtual bool onGetYUVSizes(SkISize sizes[kPlaneCount]) = 0;
+    virtual bool onGetYUVPlanes(SkISize sizes[kPlaneCount], void* planes[kPlaneCount],
+                                size_t rowBytes[kPlaneCount], SkYUVColorSpace*) = 0;
+};
+
+#endif