[skottie] External font loader tweaks

More general ResourceProvider font loading API:

1) font name argument
2) invoked unconditionally (regardless of whether an URL is present)

This provides more font control to the embedder.

Change-Id: I95557c75c2e0fe41ff68ee1b6cec8929405a74fc
Reviewed-on: https://skia-review.googlesource.com/157424
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
diff --git a/modules/skottie/gm/SkottieGM.cpp b/modules/skottie/gm/SkottieGM.cpp
index b99c337..229df62 100644
--- a/modules/skottie/gm/SkottieGM.cpp
+++ b/modules/skottie/gm/SkottieGM.cpp
@@ -27,7 +27,7 @@
 public:
     FakeWebFontProvider() : fFontData(GetResourceAsData(kWebFontResource)) {}
 
-    sk_sp<SkData> loadWebFont(const char[]) const {
+    sk_sp<SkData> loadFont(const char[], const char[]) const override {
         return fFontData;
     }