Merging to M42

ui/gfx/render_text_harfbuzz.cc

Index: ui/gfx/render_text_harfbuzz.cc
diff --git a/ui/gfx/render_text_harfbuzz.cc b/ui/gfx/render_text_harfbuzz.cc
index 1083def6baebc12a423681ad420a41ee82198ccd..aaff7ed1f04511e3ca6c0397a60585fc029a51e7 100644
--- a/ui/gfx/render_text_harfbuzz.cc
+++ b/ui/gfx/render_text_harfbuzz.cc
@@ -1267,6 +1267,19 @@ void RenderTextHarfBuzz::ShapeRun(const base::string16& text,
       default_fallback_families.begin(), default_fallback_families.end());
 #endif
 
+  // Get rid of duplicate fonts in the fallback list. We use the std::unique
+  // algorithm for this. However for this function to work we need to sort
+  // the font list as the unique algorithm relies on duplicates being adjacent.
+  // TODO(ananta)
+  // Sorting the list changes the order in which fonts are evaluated. This may
+  // cause problems in the way some characters appear. It may be best to do
+  // font fallback on the same lines as blink or skia which do this based on
+  // character glyph mapping.
+  std::sort(fallback_families.begin(), fallback_families.end());
+  fallback_families.erase(std::unique(
+      fallback_families.begin(), fallback_families.end()),
+      fallback_families.end());
+
   // Try shaping with the fallback fonts.
   for (const auto& family : fallback_families) {
     if (family == primary_family)