Implement {Start,Stop}CapturingKeyStrokes for Instant.

chrome/browser/ui/omnibox/omnibox_edit_model.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/omnibox/omnibox_edit_model.h"
 
 #include <string>
 
 #include "base/format_macros.h"
 #include "base/metrics/histogram.h"
@@ skipping 707 matching lines @@
     // that we avoid PermanentURL() here because it's not guaranteed to give us
     // the actual underlying current URL, e.g. if we're on the NTP and the
     // |permanent_text_| is empty.
     autocomplete_controller_->StartZeroSuggest(web_contents->GetURL(),
                                                user_text_);
   }
 
   NotifySearchTabHelper();
 }
 
+void OmniboxEditModel::OnFocusVisibilityChange(bool is_focus_visible) {
+  is_focus_visible_ = is_focus_visible;

[dhollowa, 2012/11/20 23:50:17]

Question: is there an invariant here that is_focus_visible_ == true implies
has_focus_ == true?  I.e. should we force it?  Or will other code be responsible
for setting has_focus_, therefore a DCHECK here?

[samarth, 2012/11/21 00:40:15]

My preference was to completely decouple focus "visibility" from whether the box
actually has focus.  Or in other words, it shouldn't matter which order you set
these in--the end result would be the same.  Tying the two together can be
tricky because plenty of things rely on focus and plenty of low-level components
can give or take focus away.

I tried to clarify this in the comments for is_focus_visible_ in
omnibox_edit_model.h.  Let me know if it's still unclear of if you prefer
different semantics.

[dhollowa, 2012/11/21 00:55:19]

That's fine if we can get away with it.  Thanks for the clarification.

+  // TODO(samarth): communicate this state to InstantController.
+}
+
 void OmniboxEditModel::OnWillKillFocus(gfx::NativeView view_gaining_focus) {
   SetInstantSuggestion(InstantSuggestion());
 
   if (InstantController* instant = controller_->GetInstant())
     instant->OmniboxLostFocus(view_gaining_focus);
 
   // TODO(jered): Rip this out along with StartZeroSuggest.
   autocomplete_controller_->StopZeroSuggest();
   NotifySearchTabHelper();
 }
 
 void OmniboxEditModel::OnKillFocus() {
   has_focus_ = false;
+  is_focus_visible_ = false;
   control_key_state_ = UP;
   paste_state_ = NONE;
 }
 
 bool OmniboxEditModel::OnEscapeKeyPressed() {
   if (has_temporary_text_) {
     AutocompleteMatch match;
     InfoForCurrentSelection(&match, NULL);
     if (match.destination_url != original_url_) {
       RevertTemporaryText(true);
@@ skipping 513 matching lines @@
 }
 
 void OmniboxEditModel::ClassifyStringForPasteAndGo(
     const string16& text,
     AutocompleteMatch* match,
     GURL* alternate_nav_url) const {
   DCHECK(match);
   AutocompleteClassifierFactory::GetForProfile(profile_)->Classify(text,
       string16(), false, false, match, alternate_nav_url);
 }