Initialize font fallback when creating DWrite font manager

include/ports/SkTypeface_win.h

Index: include/ports/SkTypeface_win.h
diff --git a/include/ports/SkTypeface_win.h b/include/ports/SkTypeface_win.h
index da728ca3c0cfc635a4f79cd209ed13e2ae26115a..8a6a8fce8927b7a7eb6b1c77bc4b1e60320e5cee 100644
--- a/include/ports/SkTypeface_win.h
+++ b/include/ports/SkTypeface_win.h
@@ -41,10 +41,12 @@ class SkFontMgr;
 class SkRemotableFontMgr;
 struct IDWriteFactory;
 struct IDWriteFontCollection;
+struct IDWriteFontFallback;
 
 SK_API SkFontMgr* SkFontMgr_New_GDI();
 SK_API SkFontMgr* SkFontMgr_New_DirectWrite(IDWriteFactory* factory = NULL,

[reed1, 2016/03/01 14:05:42]

Nit: this function is getting too many default args. Lets create a version that
takes all its parameters explicitly.

[Ilya Kulshin, 2016/03/07 23:42:04]

Reworked this patch so that the extra arg is no longer needed (that wasn't the
reason for reworking the patch).

-                                            IDWriteFontCollection* collection = NULL);
+                                            IDWriteFontCollection* collection = NULL,
+                                            IDWriteFontFallback* fallback = NULL);
 
 /**
  *  Creates an SkFontMgr which renders using DirectWrite and obtains its data