More framework support for TransferBuffers

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1534123003

Review URL: https://codereview.chromium.org/1534123003
diff --git a/src/gpu/GrResourceProvider.cpp b/src/gpu/GrResourceProvider.cpp
index 38213e6..a8bccfe 100644
--- a/src/gpu/GrResourceProvider.cpp
+++ b/src/gpu/GrResourceProvider.cpp
@@ -146,6 +146,16 @@
     return this->gpu()->createVertexBuffer(size, dynamic);
 }
 
+GrTransferBuffer* GrResourceProvider::createTransferBuffer(size_t size, TransferType type,
+                                                           uint32_t flags) {
+    if (this->isAbandoned()) {
+        return nullptr;
+    }
+
+    //bool noPendingIO = SkToBool(flags & kNoPendingIO_Flag);
+    return this->gpu()->createTransferBuffer(size, type);
+}
+
 GrBatchAtlas* GrResourceProvider::createAtlas(GrPixelConfig config,
                                               int width, int height,
                                               int numPlotsX, int numPlotsY,