A fix for Issue 3156 in chromium: "OmniBox: NavSuggest doesn't work fine when...

chrome/browser/autocomplete/autocomplete_edit.cc

 // Copyright (c) 2006-2008 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.h"
 
 #include <locale>
 
 #include "base/base_drag_source.h"
 #include "base/clipboard.h"
@@ skipping 287 matching lines @@
     UserMetrics::RecordAction(L"AcceptedKeyword", profile_);
     template_url_model->IncrementUsageCount(template_url);
   }
 
   // NOTE: We purposefully don't increment the usage count of the default search
   // engine, if applicable; see comments in template_url.h.
 }
 
 void AutocompleteEditModel::AcceptKeyword() {
   view_->OnBeforePossibleChange();
+  // NOTE: We don't need the IME composition hack in SetWindowTextAndCaretPos()
+  // here, because any active IME composition will eat <tab> characters,
+  // preventing the user from using tab-to-search until the composition is
+  // ended.
   view_->SetWindowText(L"");
   is_keyword_hint_ = false;
   keyword_ui_state_ = KEYWORD;
   view_->OnAfterPossibleChange();
   just_deleted_text_ = false;  // OnAfterPossibleChange() erroneously sets this
                                // since the edit contents have disappeared.  It
                                // doesn't really matter, but we clear it to be
                                // consistent.
   UserMetrics::RecordAction(L"AcceptedKeywordHint", profile_);
 }
@@ skipping 572 matching lines @@
   model_->SetUserText(text);
   saved_selection_for_focus_change_.cpMin = -1;
   SetWindowTextAndCaretPos(display_text, display_text.length());
   if (update_popup)
     UpdatePopup();
   TextChanged();
 }
 
 void AutocompleteEditView::SetWindowTextAndCaretPos(const std::wstring& text,
                                                     size_t caret_pos) {
+  HIMC imm_context = ImmGetContext(m_hWnd);
+  if (imm_context) {
+    // In Windows Vista, SetWindowText() automatically completes any ongoing
+    // IME composition, and updates the text of the underlying edit control.
+    // In Windows XP, however, SetWindowText() gets applied to the IME
+    // composition string if it exists, and doesn't update the underlying edit
+    // control. To avoid this, we force the IME to complete any outstanding
+    // compositions here.  This is harmless in Vista and in cases where the IME
+    // isn't composing.
+    ImmNotifyIME(imm_context, NI_COMPOSITIONSTR, CPS_COMPLETE, 0);
+    ImmReleaseContext(m_hWnd, imm_context);
+  }
+
   SetWindowText(text.c_str());
   PlaceCaretAt(caret_pos);
 }
 
 void AutocompleteEditView::SelectAll(bool reversed) {
   if (reversed)
     SetSelection(GetTextLength(), 0);
   else
     SetSelection(0, GetTextLength());
 }
@@ skipping 127 matching lines @@
     size_t user_text_length) {
   // Update the text and selection.  Because this can be called repeatedly while
   // typing, we've careful not to freeze the edit unless we really need to.
   // Also, unlike in the temporary text case above, here we don't want to update
   // the caret/selection unless we have to, since this might make the user's
   // caret position change without warning during typing.
   if (display_text == GetText())
     return false;
 
   ScopedFreeze freeze(this, GetTextObjectModel());
+  // NOTE: We don't need the IME composition hack in SetWindowTextAndCaretPos()
+  // here, because UpdatePopup() disables inline autocomplete when a
+  // composition is in progress, thus preventing us from reaching this code.
   SetWindowText(display_text.c_str());
   // Set a reversed selection to keep the caret in the same position, which
   // avoids scrolling the user's text.
   SetSelection(static_cast<LONG>(display_text.length()),
                static_cast<LONG>(user_text_length));
   TextChanged();
   return true;
 }
 
 void AutocompleteEditView::OnRevertTemporaryText() {
@@ skipping 1355 matching lines @@
 }
 
 void AutocompleteEditView::RepaintDropHighlight(int position) {
   if ((position != -1) && (position <= GetTextLength())) {
     const POINT min_loc(PosFromChar(position));
     const RECT highlight_bounds = {min_loc.x - 1, font_y_adjustment_,
         min_loc.x + 2, font_ascent_ + font_descent_ + font_y_adjustment_};
     InvalidateRect(&highlight_bounds, false);
   }
 }