Add debug option to clip each GrBatch to its device bounds

Review URL: https://codereview.chromium.org/1471083002
diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp
index 920e3c4..ad89672 100644
--- a/src/gpu/GrContext.cpp
+++ b/src/gpu/GrContext.cpp
@@ -72,11 +72,11 @@
     if (!fGpu) {
         return false;
     }
-    this->initCommon();
+    this->initCommon(options);
     return true;
 }
 
-void GrContext::initCommon() {
+void GrContext::initCommon(const GrContextOptions& options) {
     fCaps = SkRef(fGpu->caps());
     fResourceCache = new GrResourceCache(fCaps);
     fResourceCache->setOverBudgetCallback(OverBudgetCB, this);
@@ -86,7 +86,9 @@
 
     fDidTestPMConversions = false;
 
-    fDrawingManager.reset(new GrDrawingManager(this));
+    GrDrawTarget::Options dtOptions;
+    dtOptions.fClipBatchToBounds = options.fClipBatchToBounds;
+    fDrawingManager.reset(new GrDrawingManager(this, dtOptions));
 
     // GrBatchFontCache will eventually replace GrFontCache
     fBatchFontCache = new GrBatchFontCache(this);