Move texture domains onto a GrCustomStage, off of GrSamplerState.

This will require gyp changes to roll into Chrome.

http://codereview.appspot.com/6405050/



git-svn-id: http://skia.googlecode.com/svn/trunk@4641 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/effects/GrTextureDomainEffect.h b/src/gpu/effects/GrTextureDomainEffect.h
new file mode 100644
index 0000000..6157175
--- /dev/null
+++ b/src/gpu/effects/GrTextureDomainEffect.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrTextureDomainEffect_DEFINED
+#define GrTextureDomainEffect_DEFINED
+
+//#include "GrCustomStage.h"
+#include "GrSingleTextureEffect.h"
+#include "GrRect.h"
+
+class GrGLTextureDomainEffect;
+
+/**
+ * Limits a texture's lookup coordinates to a domain.
+ */
+class GrTextureDomainEffect : public GrSingleTextureEffect {
+
+public:
+
+    GrTextureDomainEffect(GrTexture*, GrRect domain);
+    virtual ~GrTextureDomainEffect();
+
+    static const char* Name() { return "TextureDomain"; }
+
+    typedef GrGLTextureDomainEffect GLProgramStage;
+
+    virtual const GrProgramStageFactory& getFactory() const SK_OVERRIDE;
+    virtual bool isEqual(const GrCustomStage&) const SK_OVERRIDE;
+
+    const GrRect& domain() const { return fTextureDomain; }
+
+protected:
+
+    GrRect fTextureDomain;
+
+private:
+
+    typedef GrSingleTextureEffect INHERITED;
+};
+
+#endif