[Mac] Don't eat tab if tab-to-search hint not visible.

chrome/browser/autocomplete/autocomplete_edit_view_mac.mm

 // Copyright (c) 2009 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/autocomplete/autocomplete_edit_view_mac.h"
 
 #include <Carbon/Carbon.h>  // kVK_Return
 #include "app/gfx/font.h"
 #include "app/resource_bundle.h"
 #include "base/clipboard.h"
@@ skipping 604 matching lines @@
   // OnAfterPossibleChange(), even if identical contents are pasted into the
   // text box.
   text_before_change_.clear();
 
   NSString* s = base::SysWideToNSString(text);
   [[field_ currentEditor] replaceCharactersInRange:selectedRange withString:s];
 
   OnAfterPossibleChange();
 }
 
+bool AutocompleteEditViewMac::OnTabPressed() {
+  if (model_->is_keyword_hint() && !model_->keyword().empty()) {
+    model_->AcceptKeyword();
+    return true;
+  }
+  return false;
+}
+
 bool AutocompleteEditViewMac::IsPopupOpen() const {
   return popup_view_->IsOpen();
 }
 
 void AutocompleteEditViewMac::OnControlKeyChanged(bool pressed) {
   model_->OnControlKeyChanged(pressed);
 }
 
 void AutocompleteEditViewMac::AcceptInput(
     WindowOpenDisposition disposition, bool for_drop) {
   model_->AcceptInput(disposition, for_drop);
 }
 
-void AutocompleteEditViewMac::AcceptKeyword() {
-  model_->AcceptKeyword();
-}
-
 void AutocompleteEditViewMac::FocusLocation() {
   [[field_ window] makeFirstResponder:field_];
   DCHECK_EQ([field_ currentEditor], [[field_ window] firstResponder]);
 }
 
 // TODO(shess): Copied from autocomplete_edit_view_win.cc.  Could this
 // be pushed into the model?
 std::wstring AutocompleteEditViewMac::GetClipboardText(Clipboard* clipboard) {
   // autocomplete_edit_view_win.cc assumes this can never happen, we
   // will too.
@@ skipping 66 matching lines @@
     edit_view_->OnUpOrDownKeyPressed(true, true);
     return YES;
   }
 
   if (cmd == @selector(cancelOperation:)) {
     edit_view_->OnEscapeKeyPressed();
     return YES;
   }
 
   if (cmd == @selector(insertTab:)) {
-    edit_view_->AcceptKeyword();
-    return YES;
+    if (edit_view_->OnTabPressed()) {
+      return YES;
+    }
   }
 
   // |-noop:| is sent when the user presses Cmd+Return. Override the no-op
   // behavior with the proper WindowOpenDisposition.
   NSEvent* event = [NSApp currentEvent];
   if (cmd == @selector(insertNewline:) ||
      (cmd == @selector(noop:) && [event keyCode] == kVK_Return)) {
     WindowOpenDisposition disposition =
         event_utils::WindowOpenDispositionFromNSEvent(event);
     edit_view_->AcceptInput(disposition, false);
@@ skipping 61 matching lines @@
 // prepended and ".com" appended.  This calls down to
 // AutocompleteEditModel::OnControlKeyChanged() so that it can change
 // the popup to reflect this.  See autocomplete_edit.cc
 // OnControlKeyChanged() and OnAfterPossibleChange().
 - (void)control:(NSControl*)control flagsChanged:(NSEvent*)theEvent {
   BOOL controlFlag = ([theEvent modifierFlags]&NSControlKeyMask) != 0;
   edit_view_->OnControlKeyChanged(controlFlag);
 }
 
 @end