gm: add a flag to force perspective usage in all gms

gm/gm.h

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef skiagm_DEFINED
 #define skiagm_DEFINED
 
@@ skipping 56 matching lines @@
         }
         SkScalar height() {
             return SkIntToScalar(this->getISize().height());
         }
 
         // TODO(vandebo) Instead of exposing this, we should run all the GMs
         // with and without an initial transform.
         // Most GMs will return the identity matrix, but some PDFs tests
         // require setting the initial transform.
         SkMatrix getInitialTransform() const {
-            return this->onGetInitialTransform();
+            SkMatrix matrix = fStarterMatrix;
+            matrix.preConcat(this->onGetInitialTransform());
+            return matrix;
         }
 
         SkColor getBGColor() const { return fBGColor; }
         void setBGColor(SkColor);
 
         // helper: fill a rect in the specified color based on the
         // GM's getISize bounds.
         void drawSizeBounds(SkCanvas*, SkColor);
 
         static void SetResourcePath(const char* resourcePath) {
@@ skipping 11 matching lines @@
 
         bool isCanvasDeferred() const { return fCanvasIsDeferred; }
         void setCanvasIsDeferred(bool isDeferred) {
             fCanvasIsDeferred = isDeferred;
         }
 
 #if SK_SUPPORT_GPU
         static GrContext* GetGr(/*very nearly const*/ SkCanvas*);
 #endif
 
+    const SkMatrix& getStarterMatrix() { return fStarterMatrix; }
+    void setStarterMatrix(const SkMatrix& matrix) {
+        fStarterMatrix = matrix;
+    }
+
     protected:
         static SkString gResourcePath;
 
         virtual void onOnceBeforeDraw() {}
         virtual void onDraw(SkCanvas*) = 0;
         virtual void onDrawBackground(SkCanvas*);
         virtual SkISize onISize() = 0;
         virtual SkString onShortName() = 0;
         virtual uint32_t onGetFlags() const { return 0; }
         virtual SkMatrix onGetInitialTransform() const { return SkMatrix::I(); }
 
     private:
         SkString fShortName;
         SkColor  fBGColor;
         bool     fCanvasIsDeferred; // work-around problem in srcmode.cpp
         bool     fHaveCalledOnceBeforeDraw;
         bool     fIgnoreFailures; // whether to file any failures as failure-ignored
+        SkMatrix fStarterMatrix;
     };
 
     typedef SkTRegistry<GM*(*)(void*)> GMRegistry;
 }
 
 #endif