Prevent infinite loop about itemizing text in RenderTextHarfBuzz.

ui/gfx/render_text_unittest.cc

Index: ui/gfx/render_text_unittest.cc
diff --git a/ui/gfx/render_text_unittest.cc b/ui/gfx/render_text_unittest.cc
index fa544f3e1bbf8b4785b9545a59c41f236dbd9b1e..caccf009ae284d2f16ef79d3995f65bc93b2c16f 100644
--- a/ui/gfx/render_text_unittest.cc
+++ b/ui/gfx/render_text_unittest.cc
@@ -2577,6 +2577,15 @@ TEST_F(RenderTextTest, HarfBuzz_EmptyRun) {
   EXPECT_EQ(Range(0, 0), glyphs);
 }
 
+TEST_F(RenderTextTest, HarfBuzz_InfiniteLoop) {

[Daniel Erat, 2015/03/17 23:26:00]

nit: mind adding a comment pointing back at the bug?

[Jun Mukai, 2015/03/18 01:32:05]

added

+  RenderTextHarfBuzz render_text;
+  render_text.SetObscured(true);
+  render_text.SetText(UTF8ToUTF16("\xF0\x9F\x98\x81y"));
+  render_text.ApplyStyle(BOLD, true, Range(1, 3));
+  gfx::Canvas canvas;
+  render_text.Draw(&canvas);
+}
+
 // Ensure a string fits in a display rect with a width equal to the string's.
 TEST_F(RenderTextTest, StringFitsOwnWidth) {
   scoped_ptr<RenderText> render_text(RenderText::CreateInstance());