Disable canvas flipping for Extensions icon

Only affects ExtensionsToolbarContainer which is under a flag.

Bug: chromium:1006192
Change-Id: I0e414881815635b7a4810930cc0ebd142ef493ac
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1815594
Commit-Queue: Peter Boström <pbos@chromium.org>
Commit-Queue: Caroline Rising <corising@chromium.org>
Auto-Submit: Peter Boström <pbos@chromium.org>
Reviewed-by: Caroline Rising <corising@chromium.org>
Cr-Commit-Position: refs/heads/master@{#698643}

chrome/browser/ui/views/extensions/extensions_toolbar_container.cc

@@ -48,6 +48,8 @@ ExtensionsToolbarContainer::ExtensionsToolbarContainer(Browser* browser)
       .SetDefault(views::kMarginsKey,
                   gfx::Insets(0, GetLayoutConstant(TOOLBAR_ELEMENT_PADDING)));
   model_observer_.Add(model_);
+  // Do not flip the Extensions icon in RTL.
+  extensions_button_->EnableCanvasFlippingForRTLUI(false);
   AddMainButton(extensions_button_);
   CreateActions();
 }