move GrMalloc, GrFree, Gr_bzero to their sk equivalents

BUG=
R=bsalomon@google.com

Review URL: https://codereview.chromium.org/23566022

git-svn-id: http://skia.googlecode.com/svn/trunk@11486 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrGpu.cpp b/src/gpu/GrGpu.cpp
index a4aa00e..910c571 100644
--- a/src/gpu/GrGpu.cpp
+++ b/src/gpu/GrGpu.cpp
@@ -276,14 +276,14 @@
                 fill_indices(indices, MAX_QUADS);
                 fQuadIndexBuffer->unlock();
             } else {
-                indices = (uint16_t*)GrMalloc(SIZE);
+                indices = (uint16_t*)sk_malloc_throw(SIZE);
                 fill_indices(indices, MAX_QUADS);
                 if (!fQuadIndexBuffer->updateData(indices, SIZE)) {
                     fQuadIndexBuffer->unref();
                     fQuadIndexBuffer = NULL;
                     GrCrash("Can't get indices into buffer!");
                 }
-                GrFree(indices);
+                sk_free(indices);
             }
         }
     }