Add skia extension to allow setting default fontmgr on linux. Use it to allow the linux blimp clien…

skia/ext/fontmgr_default_linux.cc

Index: skia/ext/fontmgr_default_linux.cc
diff --git a/skia/ext/fontmgr_default_linux.cc b/skia/ext/fontmgr_default_linux.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c88d592a4ce37190a45d3548870f9d77d1824752
--- /dev/null
+++ b/skia/ext/fontmgr_default_linux.cc
@@ -0,0 +1,25 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "skia/ext/fontmgr_default_linux.h"
+
+#include "third_party/skia/include/ports/SkFontConfigInterface.h"
+#include "third_party/skia/include/ports/SkFontMgr.h"
+#include "third_party/skia/include/ports/SkFontMgr_FontConfigInterface.h"
+
+namespace {
+sk_sp<SkFontMgr> g_default_fontmgr;
+}  // namespace
+
+void SetDefaultSkiaFactory(sk_sp<SkFontMgr> fontmgr) {
+  g_default_fontmgr = fontmgr;
+}
+
+SK_API SkFontMgr* SkFontMgr::Factory() {
+  if (g_default_fontmgr) {
+    return g_default_fontmgr.get();

[bungeman-chromium, 2016/11/14 18:10:03]

This needs to return a reference (sorry again about not already making this
method return sk_sp yet). As a result, this needs to be

return SkRef(g_default_fontmgr.get());

otherwise the global isn't holding a reference anymore.

[steimel, 2016/11/14 18:15:11]

Done.

+  }
+  sk_sp<SkFontConfigInterface> fci(SkFontConfigInterface::RefGlobal());
+  return fci ? SkFontMgr_New_FCI(std::move(fci)) : nullptr;
+}