sync compositor: pass simple gfx types by const ref

See bug for reasoning

BUG=159273

Review URL: https://codereview.chromium.org/1417893006

Cr-Commit-Position: refs/heads/master@{#356653}
void BrowserViewRenderer::EnableOnNewPicture(bool enabled) {
  on_new_picture_enable_ = enabled;
}

void BrowserViewRenderer::EnableOnNewPicture(bool enabled) {
  on_new_picture_enable_ = enabled;
}
