Rename GrContext's newDrawContext & drawContext to makeDrawContext

These both return sk_sp.

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2186073002

Review-Url: https://codereview.chromium.org/2186073002
diff --git a/src/effects/SkDisplacementMapEffect.cpp b/src/effects/SkDisplacementMapEffect.cpp
index 9370a9f..df4103c 100644
--- a/src/effects/SkDisplacementMapEffect.cpp
+++ b/src/effects/SkDisplacementMapEffect.cpp
@@ -336,8 +336,8 @@
         matrix.setTranslate(-SkIntToScalar(colorBounds.x()), -SkIntToScalar(colorBounds.y()));
 
         sk_sp<GrDrawContext> drawContext(
-            context->newDrawContext(SkBackingFit::kApprox, bounds.width(), bounds.height(),
-                                    kSkia8888_GrPixelConfig, sk_ref_sp(source->getColorSpace())));
+            context->makeDrawContext(SkBackingFit::kApprox, bounds.width(), bounds.height(),
+                                     kSkia8888_GrPixelConfig, sk_ref_sp(source->getColorSpace())));
         if (!drawContext) {
             return nullptr;
         }