Re-land: "RenderTextWin: Break runs between any two characters that are not in the same code block"

ui/gfx/render_text_unittest.cc

 // Copyright (c) 2012 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 "ui/gfx/render_text.h"
 
 #include <algorithm>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/stringprintf.h"
@@ skipping 1633 matching lines @@
     const int expected_width = render_text->GetStringSize().width();
     render_text->MoveCursorTo(SelectionModel(ui::Range(0, 1), CURSOR_FORWARD));
     EXPECT_EQ(expected_width, render_text->GetStringSize().width());
     // Draw the text. It shouldn't hit any DCHECKs or crash.
     // See http://crbug.com/214150
     render_text->Draw(&canvas);
     render_text->MoveCursorTo(SelectionModel(0, CURSOR_FORWARD));
   }
 }
 
+#if defined(OS_WIN)
+TEST_F(RenderTextTest, Win_BreakRunsByUnicodeBlocks) {
+  scoped_ptr<RenderTextWin> render_text(
+      static_cast<RenderTextWin*>(RenderText::CreateInstance()));
+
+  render_text->SetText(WideToUTF16(L"x\x25B6y"));
+  render_text->EnsureLayout();
+  ASSERT_EQ(3U, render_text->runs_.size());
+  EXPECT_EQ(Range(0, 1), render_text->runs_[0]->range);
+  EXPECT_EQ(Range(1, 2), render_text->runs_[1]->range);
+  EXPECT_EQ(Range(2, 3), render_text->runs_[2]->range);
+
+  render_text->SetText(WideToUTF16(L"x \x25B6 y"));
+  render_text->EnsureLayout();
+  ASSERT_EQ(3U, render_text->runs_.size());
+  EXPECT_EQ(Range(0, 2), render_text->runs_[0]->range);
+  EXPECT_EQ(Range(2, 3), render_text->runs_[1]->range);
+  EXPECT_EQ(Range(3, 5), render_text->runs_[2]->range);
+
+}
+#endif  // !defined(OS_WIN)
+
 }  // namespace gfx