Move inval dedup to Window for wider usages.

tools/viewer/Viewer.cpp

 /*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 #include "Viewer.h"
 
 #include "GMSlide.h"
@@ skipping 301 matching lines @@
         }
         case Window::kDown_InputState: {
             fGesture.touchBegin(castedOwner, touchPoint.fX, touchPoint.fY);
             break;
         }
         case Window::kMove_InputState: {
             fGesture.touchMoved(castedOwner, touchPoint.fX, touchPoint.fY);
             break;
         }
     }
-    fWindow->inval();
+    fWindow->checkAndInval();
     return true;
 }
 
 void Viewer::drawStats(SkCanvas* canvas) {
     static const float kPixelPerMS = 2.0f;
     static const int kDisplayWidth = 130;
     static const int kDisplayHeight = 100;
     static const int kDisplayPadding = 10;
     static const int kGraphPadding = 3;
     static const SkScalar kBaseMS = 1000.f / 60.f;  // ms/frame to hit 60 fps
@@ skipping 42 matching lines @@
     // Record measurements
     fMeasurements[fCurrentMeasurement++] = ms;
     fCurrentMeasurement &= (kMeasurementCount - 1);  // fast mod
     SkASSERT(fCurrentMeasurement < kMeasurementCount);
 
     fAnimTimer.updateTime();
     if (fSlides[fCurrentSlide]->animate(fAnimTimer) || fDisplayStats) {
         fWindow->inval();
     }
 }