Add onfocuschange to the Extended Search API, with associated isFocused attribute.

chrome/browser/ui/search/instant_controller.cc

Index: chrome/browser/ui/search/instant_controller.cc
diff --git a/chrome/browser/ui/search/instant_controller.cc b/chrome/browser/ui/search/instant_controller.cc
index 02ba4d3c6a367e313050d415e01b35bf01b8838f..89224e263170a01caf9bc9171ec2284e15756411 100644
--- a/chrome/browser/ui/search/instant_controller.cc
+++ b/chrome/browser/ui/search/instant_controller.cc
@@ -944,17 +944,32 @@ void InstantController::OmniboxFocusChanged(
       instant_tab_->KeyCaptureChanged(is_key_capture_enabled);
   }
 
+  bool focus_changed = false;
   if (state == OMNIBOX_FOCUS_VISIBLE && old_focus_state == OMNIBOX_FOCUS_NONE) {
     // If the user explicitly focused the omnibox, then create the overlay if
     // it doesn't exist. If we're using a fallback overlay, try loading the
     // remote overlay again.
     if (!overlay_ || (overlay_->IsLocal() && !use_local_page_only_))
       ResetOverlay(GetInstantURL());
+    focus_changed = true;
   } else if (state == OMNIBOX_FOCUS_NONE &&
              old_focus_state != OMNIBOX_FOCUS_NONE) {
     // If the focus went from the omnibox to outside the omnibox, commit or
     // discard the overlay.
     OmniboxLostFocus(view_gaining_focus);
+    focus_changed = true;
+  }

[melevin, 2013/05/09 16:41:11]

Instead of using the "focus_changed" variable you could also early return here
in an "else" block.

[Donn Denman, 2013/05/13 18:00:39]

Given Samarth's comments, I think this will no longer be an issue.  For the
record, I prefer to avoid early returns, especially in the middle of functions,
because they are easy to miss.

+
+  // If the focus changed, notify the page.
+  if (focus_changed && state != OMNIBOX_FOCUS_INVISIBLE) {

[samarth, 2013/05/10 00:55:32]

We should do the "did focus actually change" check in the renderer
(searchbox.cc) rather than here.   There is a SearchBox instance per page and so
by doing the checks there rather than here (which is per-browser), we can ensure
the page always gets an update when necessary.

Also, instead of having separate KeyCaptureChanged and FocusChanged IPCs, lets
just use a single IPC that sends the focus state enum value (and change reason),
and move the logic for whether we should send a keycapture into the SearchBox
code.

[Donn Denman, 2013/05/13 18:00:39]

Done.

+    // TODO(donnd): fix multiple notifications clicking the Google search box.
+    bool is_focused = omnibox_focus_state_ == OMNIBOX_FOCUS_VISIBLE;
+    if (overlay_)
+      overlay_->FocusChanged(is_focused);
+    if (ntp_)
+      ntp_->FocusChanged(is_focused);
+    if (instant_tab_)
+      instant_tab_->FocusChanged(is_focused);
   }
 }