Always initialize |m_totalWidth| in HarfBuzzShaper::shape.

R=leviw@chromium.org
BUG=476647

Review URL: https://codereview.chromium.org/1108663003

git-svn-id: svn://svn.chromium.org/blink/trunk@194541 bbb929c8-8fbe-4397-9dbb-9b2b20218538
CachedShapingResults::CachedShapingResults(hb_buffer_t* harfBuzzBuffer, const Font* fontData, hb_direction_t dirData, const String& newLocale)
    : buffer(harfBuzzBuffer)
    , font(*fontData)
    , dir(dirData)
    , locale(newLocale)
{
}

CachedShapingResults::CachedShapingResults(hb_buffer_t* harfBuzzBuffer, const Font* fontData, hb_direction_t dirData, const String& newLocale)
    : buffer(harfBuzzBuffer)
    , font(*fontData)
    , dir(dirData)
    , locale(newLocale)
{
}
