Fix a new clang warning:

Fix a new clang warning:

third_party/skia/src/ports/SkFontHost_FreeType.cpp:957:7:error: switch case is in protected scope
      default:
      ^
third_party/skia/src/ports/SkFontHost_FreeType.cpp:918:17: note: jump bypasses variable initialization
        FT_BBox bbox;
                ^
third_party/skia/src/ports/SkFontHost_FreeType.cpp:946:7:error: switch case is in protected scope
      case FT_GLYPH_FORMAT_BITMAP:
      ^
third_party/skia/src/ports/SkFontHost_FreeType.cpp:918:17: note: jump bypasses variable initialization
        FT_BBox bbox;
                ^
2 errors generated.

This is arguably a false positive, but since |bbox| can only safely be used in
the first case branch, it's a good idea to scope it to there anyway. This is
the only instance this warning occurs in all of chrome.

[thakis, 2011-05-24 03:25:28]

This is blocking the next clang roll.

[Steve VanDeBogart, 2011-05-24 05:16:51]

LGTM

[reed1, 2011-05-24 19:32:03]

LGTM