Implement text rendering with NVPR

include/gpu/GrContext.h

Index: include/gpu/GrContext.h
diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h
index 41ee15917f44c60b71a3aecd7044debeea61aa57..bb7c77cdb7d3da1fad33638b5c65be7422752675 100644
--- a/include/gpu/GrContext.h
+++ b/include/gpu/GrContext.h
@@ -36,6 +36,7 @@ class GrResourceEntry;
 class GrResourceCache;
 class GrStencilBuffer;
 class GrTestTarget;
+class GrTextContext;
 class GrTextureParams;
 class GrVertexBuffer;
 class GrVertexBufferAllocPool;
@@ -191,6 +192,16 @@ public:
      */
     GrCacheable* findAndRefCachedResource(const GrResourceKey&);
 
+    /**
+     * Creates a new text rendering context that is optimal for the
+     * render target and the context. Caller assumes the ownership
+     * of the returned object. The returned object must be deleted
+     * before the context is destroyed.
+     */
+    GrTextContext* createTextContext(GrRenderTarget*,
+                                     const SkDeviceProperties&,
+                                     bool enableDistanceFieldFonts);
+
     ///////////////////////////////////////////////////////////////////////////
     // Textures
 
@@ -1007,6 +1018,7 @@ private:
     // addExistingTextureToCache
     friend class GrTexture;
     friend class GrStencilAndCoverPathRenderer;
+    friend class GrStencilAndCoverTextContext;
 
     // Add an existing texture to the texture cache. This is intended solely
     // for use with textures released from an GrAutoScratchTexture.