Make Google Search autocomplete provider cursor aware.

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/auto_reset.h"
 #include "base/format_macros.h"
@@ skipping 438 matching lines @@
     action_predictor->ClearTransitionalMatches();
 }
 
 void OmniboxEditModel::StartAutocomplete(
     bool has_selected_text,
     bool prevent_inline_autocomplete) const {
   ClearPopupKeywordMode();
 
   bool keyword_is_selected = KeywordIsSelected();
   popup_->SetHoveredLine(OmniboxPopupModel::kNoMatch);
+
+  size_t cursor_position;
+  if (inline_autocomplete_text_.empty()) {
+    // Cursor position is equivalent to the current selection's end.
+    size_t start;
+    view_->GetSelectionBounds(&start, &cursor_position);
+  } else {
+    // There are some cases where StartAutocomplete() may be called
+    // with non-empty |inline_autocomplete_text_|.  In such cases, we cannot
+    // use the current selection, because it could result with the cursor
+    // position past the last character from the user text.  Instead,

[Peter Kasting, 2012/12/18 03:01:01]

In theory, inline autocompletions are supposed to be reverse-selected, so you'd
still get the selection "end" at the end of the user's typing.  (That's true on
Windows for sure, I haven't tested the other platforms.)  It sounds like maybe
you found somewhere that isn't the case?

[Bart N., 2012/12/18 23:47:39]

Yes. See http://crbug.com/165961. I've updated the comment.

+    // we assume that the cursor is simply at the end of input.
+    // One example is when user presses Ctrl key while having a highlighted
+    // inline autocomplete text.
+    // TODO: Rethink how we are going to handle this case to avoid
+    // inconsistent behavior when user presses Ctrl key.
+    cursor_position = user_text_.length();
+  }
+
   // We don't explicitly clear OmniboxPopupModel::manually_selected_match, as
   // Start ends up invoking OmniboxPopupModel::OnResultChanged which clears it.
-  autocomplete_controller_->Start(
-      user_text_, GetDesiredTLD(),
+  autocomplete_controller_->Start(AutocompleteInput(
+      user_text_, cursor_position, GetDesiredTLD(),
       prevent_inline_autocomplete || just_deleted_text_ ||
       (has_selected_text && inline_autocomplete_text_.empty()) ||
       (paste_state_ != NONE), keyword_is_selected,
       keyword_is_selected || allow_exact_keyword_match_,
-      AutocompleteInput::ALL_MATCHES);
+      AutocompleteInput::ALL_MATCHES));
 }
 
 void OmniboxEditModel::StopAutocomplete() {
   autocomplete_controller_->Stop(true);
 }
 
 bool OmniboxEditModel::CanPasteAndGo(const string16& text) const {
   if (!view_->command_updater()->IsCommandEnabled(IDC_OPEN_CURRENT_URL))
     return false;
 
@@ skipping 838 matching lines @@
     instant->OmniboxFocusChanged(state, reason, NULL);
 
   // Update state and notify view if the omnibox has focus and the caret
   // visibility changed.
   const bool was_caret_visible = is_caret_visible();
   focus_state_ = state;
   if (focus_state_ != OMNIBOX_FOCUS_NONE &&
       is_caret_visible() != was_caret_visible)
     view_->ApplyCaretVisibility();
 }