Use calloc to allocate data that will be uploaded to vertex/index buffers in Chrome

src/gpu/gl/GrGLBufferImpl.cpp

Index: src/gpu/gl/GrGLBufferImpl.cpp
diff --git a/src/gpu/gl/GrGLBufferImpl.cpp b/src/gpu/gl/GrGLBufferImpl.cpp
index 5d5ca88b2df920f01524ebdbe11be3312448b383..0e2990e7f9fcf1a802cd45e8da659a66d705bad0 100644
--- a/src/gpu/gl/GrGLBufferImpl.cpp
+++ b/src/gpu/gl/GrGLBufferImpl.cpp
@@ -25,7 +25,11 @@ GrGLBufferImpl::GrGLBufferImpl(GrGLGpu* gpu, const Desc& desc, GrGLenum bufferTy
     , fBufferType(bufferType)
     , fMapPtr(NULL) {
     if (0 == desc.fID) {
-        fCPUData = sk_malloc_flags(desc.fSizeInBytes, SK_MALLOC_THROW);
+        if (gpu->caps()->mustClearUploadedBufferData()) {
+            fCPUData = sk_calloc_throw(desc.fSizeInBytes);
+        } else {
+            fCPUData = sk_malloc_flags(desc.fSizeInBytes, SK_MALLOC_THROW);
+        }
         fGLSizeInBytes = 0;
     } else {
         fCPUData = NULL;