Add desired width & height to drawContext (as opposed to using the width & height of the RT)

include/gpu/GrDrawContext.h

 /*
  * 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 GrDrawContext_DEFINED
 #define GrDrawContext_DEFINED
 
@@ skipping 246 matching lines @@
         return fRenderTarget->isStencilBufferMultisampled();
     }
     bool isUnifiedMultisampled() const { return fRenderTarget->isUnifiedMultisampled(); }
     bool hasMixedSamples() const { return fRenderTarget->hasMixedSamples(); }
 
     bool mustUseHWAA(const GrPaint& paint) const {
         return paint.isAntiAlias() && fRenderTarget->isUnifiedMultisampled();
     }
 
     const GrSurfaceDesc& desc() const { return fRenderTarget->desc(); }
-    int width() const { return fRenderTarget->width(); }
-    int height() const { return fRenderTarget->height(); }
+    int width() const { return fWidth; }
+    int height() const { return fHeight; }
     GrPixelConfig config() const { return fRenderTarget->config(); }
     int numColorSamples() const { return fRenderTarget->numColorSamples(); }
     bool isGammaCorrect() const { return fSurfaceProps.isGammaCorrect(); }
     const SkSurfaceProps& surfaceProps() const { return fSurfaceProps; }
 
     bool wasAbandoned() const;
 
     GrRenderTarget* accessRenderTarget() { return fRenderTarget.get(); }
 
     sk_sp<GrRenderTarget> renderTarget() { return fRenderTarget; }
 
     sk_sp<GrTexture> asTexture() { return sk_ref_sp(fRenderTarget->asTexture()); }
 
     // Provides access to functions that aren't part of the public API.
     GrDrawContextPriv drawContextPriv();
     const GrDrawContextPriv drawContextPriv() const;
 
     GrAuditTrail* auditTrail() { return fAuditTrail; }
 
 protected:
-    GrDrawContext(GrContext*, GrDrawingManager*, sk_sp<GrRenderTarget>,
+    GrDrawContext(GrContext*, GrDrawingManager*, int width, int height, sk_sp<GrRenderTarget>,
                   const SkSurfaceProps* surfaceProps, GrAuditTrail*, GrSingleOwner*);
 
     GrDrawingManager* drawingManager() { return fDrawingManager; }
 
     SkDEBUGCODE(GrSingleOwner* singleOwner() { return fSingleOwner; })
     SkDEBUGCODE(void validate() const;)
 
 private:
     friend class GrAtlasTextBlob; // for access to drawBatch
     friend class GrStencilAndCoverTextContext; // for access to drawBatch
@@ skipping 43 matching lines @@
                           const SkPath& path,
                           const GrStyle& style);
 
     // This entry point allows the GrTextContext-derived classes to add their batches to
     // the drawTarget.
     void drawBatch(const GrPipelineBuilder& pipelineBuilder, const GrClip&, GrDrawBatch* batch);
 
     GrDrawTarget* getDrawTarget();
 
     GrDrawingManager*                 fDrawingManager;
+
+    // The width & height of the drawContext may be less than the width & height of the 
+    // underlying renderTarget
+    int                               fWidth;
+    int                               fHeight;
     sk_sp<GrRenderTarget>             fRenderTarget;
 
     // In MDB-mode the drawTarget can be closed by some other drawContext that has picked
     // it up. For this reason, the drawTarget should only ever be accessed via 'getDrawTarget'.
     GrDrawTarget*                     fDrawTarget;
     SkAutoTDelete<GrAtlasTextContext> fAtlasTextContext;
     GrContext*                        fContext;
     GrInstancedPipelineInfo           fInstancedPipelineInfo;
 
     SkSurfaceProps                    fSurfaceProps;
     GrAuditTrail*                     fAuditTrail;
 
     // In debug builds we guard against improper thread handling
     SkDEBUGCODE(mutable GrSingleOwner* fSingleOwner;)
 };
 
 #endif