[omnibox] [rich-autocompletion] Show context menu on right click.

Rich autocompletion added the |omnibox_additional_text_view_| label
adjacent to the |omnibox_view_| in the LocationBarView. When the
|omnibox_view_| displays a suggestion's contents, the label (if visible)
displays its description and vice versa. The LocationBarView directs
mouse button events from |omnibox_additional_text_view_| to
|omnibox_view_| so that, e.g., clicking the former will focus the
latter.

Specifically, the LocationBarView already directs the OnMousePressed,
OnMouseDragged, and OnMouseReleased events. This CL also adds
ShowContextMenu to be directed.

Bug: 1150010, 1062446
Change-Id: I639177a65abdb70e2c34322fb5217827b02c142e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2586766Reviewed-by: Tommy Li <tommycli@chromium.org>
Commit-Queue: manuk hovanesian <manukh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836856}

chrome/browser/ui/views/location_bar/location_bar_view.cc

@@ -194,6 +194,11 @@ void LocationBarView::Init() {
       is_popup_mode_, this, font_list);
   omnibox_view->Init();
   omnibox_view_ = AddChildView(std::move(omnibox_view));
+  // LocationBarView directs mouse button events from
+  // |omnibox_additional_text_view_| to |omnibox_view_| so that e.g., clicking
+  // the former will focus the latter. In order to receive |ShowContextMenu()|
+  // requests, LocationBarView must have a context menu controller.
+  set_context_menu_controller(omnibox_view_->context_menu_controller());
 
   // Initiate the Omnibox additional-text label.
   if (OmniboxFieldTrial::RichAutocompletionShowAdditionalText()) {
@@ -1099,6 +1104,11 @@ void LocationBarView::OnMouseExited(const ui::MouseEvent& event) {
   OnOmniboxHovered(false);
 }
 
+void LocationBarView::ShowContextMenu(const gfx::Point& p,
+                                      ui::MenuSourceType source_type) {
+  omnibox_view_->ShowContextMenu(p, source_type);
+}
+
 void LocationBarView::WriteDragDataForView(views::View* sender,
                                            const gfx::Point& press_pt,
                                            OSExchangeData* data) {

chrome/browser/ui/views/location_bar/location_bar_view.h

@@ -301,13 +301,16 @@ class LocationBarView : public LocationBar,
   void OnVisibleBoundsChanged() override;
   void OnFocus() override;
   void OnPaintBorder(gfx::Canvas* canvas) override;
-  // LocationBarView directs mouse button events from OmniboxAdditionalTextView
-  // to OmniboxView so that e.g., clicking the former will focus the latter.
+  // LocationBarView directs mouse button events from
+  // |omnibox_additional_text_view_| to |omnibox_view_| so that e.g., clicking
+  // the former will focus the latter.
   bool OnMousePressed(const ui::MouseEvent& event) override;
   bool OnMouseDragged(const ui::MouseEvent& event) override;
   void OnMouseReleased(const ui::MouseEvent& event) override;
   void OnMouseMoved(const ui::MouseEvent& event) override;
   void OnMouseExited(const ui::MouseEvent& event) override;
+  void ShowContextMenu(const gfx::Point& p,
+                       ui::MenuSourceType source_type) override;
 
   // views::DragController:
   void WriteDragDataForView(View* sender,