Move unusual character block logic to a helper function

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 138cd548c00e1653f8d85407b4b2c32cfdf719a5..368ec11c93740e2e8e2c82a61fa907c8e1e354c2 100644
--- a/ui/gfx/render_text_harfbuzz.cc
+++ b/ui/gfx/render_text_harfbuzz.cc
@@ -277,6 +277,27 @@ bool IsUnusualBlockCode(UBlockCode block_code) {
          block_code == UBLOCK_MISCELLANEOUS_SYMBOLS;
 }
 
+// Returns the index of the first unusual character after a usual character or
+// vice versa. Unusual characters are defined by |IsUnusualBlockCode|.
+size_t FindUnusualCharacter(const base::string16& text,
+                            size_t run_start,
+                            size_t run_break) {
+  const int32 run_length = static_cast<int32>(run_break - run_start);
+  base::i18n::UTF16CharIterator iter(text.c_str() + run_start,
+                                     run_length);
+  const UBlockCode first_block_code = ublock_getCode(iter.get());
+  const bool first_block_unusual = IsUnusualBlockCode(first_block_code);
+  while (iter.Advance() && iter.array_pos() < run_length) {
+    const UBlockCode current_block_code = ublock_getCode(iter.get());
+    if (current_block_code != first_block_code &&
+        (first_block_unusual || IsUnusualBlockCode(current_block_code))) {
+      run_break = run_start + iter.array_pos();

[msw, 2014/06/10 18:03:15]

Just return run_start + iter.array_pos() here.

[ckocagil, 2014/06/11 07:49:37]

Done.

+      break;
+    }
+  }
+  return run_break;
+}
+
 // If the given scripts match, returns the one that isn't USCRIPT_COMMON or
 // USCRIPT_INHERITED, i.e. the more specific one. Otherwise returns
 // USCRIPT_INVALID_CODE.
@@ -904,22 +925,8 @@ void RenderTextHarfBuzz::ItemizeText() {
       // Break runs adjacent to character substrings in certain code blocks.
       // This avoids using their fallback fonts for more characters than needed,
       // in cases like "\x25B6 Media Title", etc. http://crbug.com/278913
-      if (run_break > run->range.start()) {
-        const size_t run_start = run->range.start();
-        const int32 run_length = static_cast<int32>(run_break - run_start);
-        base::i18n::UTF16CharIterator iter(text.c_str() + run_start,
-                                           run_length);
-        const UBlockCode first_block_code = ublock_getCode(iter.get());
-        const bool first_block_unusual = IsUnusualBlockCode(first_block_code);
-        while (iter.Advance() && iter.array_pos() < run_length) {
-          const UBlockCode current_block_code = ublock_getCode(iter.get());
-          if (current_block_code != first_block_code &&
-              (first_block_unusual || IsUnusualBlockCode(current_block_code))) {
-            run_break = run_start + iter.array_pos();
-            break;
-          }
-        }
-      }
+      if (run_break > run->range.start())
+        run_break = FindUnusualCharacter(text, run->range.start(), run_break);
     }
 
     DCHECK(IsValidCodePointIndex(text, run_break));