[Linux] Improve preedit string and Instant suggestion support in omnibox.

chrome/browser/autocomplete/autocomplete_edit_view_gtk.h

Index: chrome/browser/autocomplete/autocomplete_edit_view_gtk.h
diff --git a/chrome/browser/autocomplete/autocomplete_edit_view_gtk.h b/chrome/browser/autocomplete/autocomplete_edit_view_gtk.h
index 34dd01c51985198db75e00ff1702823371860daa..07e0ed3866325905e02603e8220f1e6980c3f870 100644
--- a/chrome/browser/autocomplete/autocomplete_edit_view_gtk.h
+++ b/chrome/browser/autocomplete/autocomplete_edit_view_gtk.h
@@ -174,6 +174,12 @@ class AutocompleteEditViewGtk : public AutocompleteEditView,
                      GtkTextBuffer*, GtkTextIter*, const gchar*, gint);
   CHROMEG_CALLBACK_0(AutocompleteEditViewGtk, void,
                      HandleKeymapDirectionChanged, GdkKeymap*);
+  CHROMEG_CALLBACK_2(AutocompleteEditViewGtk, void, HandleDeleteRange,
+                     GtkTextBuffer*, GtkTextIter*, GtkTextIter*);
+  // Unlike above HandleMarkSet and HandleMarkSetAfter, this handler will always
+  // be connected to the signal.
+  CHROMEG_CALLBACK_2(AutocompleteEditViewGtk, void, HandleMarkSetAlways,
+                     GtkTextBuffer*, GtkTextIter*, GtkTextMark*);
 
   CHROMEGTK_CALLBACK_1(AutocompleteEditViewGtk, gboolean, HandleKeyPress,
                        GdkEventKey*);
@@ -214,12 +220,16 @@ class AutocompleteEditViewGtk : public AutocompleteEditView,
   // listen to focus change events on it.
   CHROMEGTK_CALLBACK_1(AutocompleteEditViewGtk, void, HandleHierarchyChanged,
                        GtkWidget*);
-  CHROMEGTK_CALLBACK_1(AutocompleteEditViewGtk, gboolean,
-                       HandleInstantViewButtonPress, GdkEventButton*);
-#if GTK_CHECK_VERSION(2,20,0)
+#if GTK_CHECK_VERSION(2, 20, 0)
   CHROMEGTK_CALLBACK_1(AutocompleteEditViewGtk, void, HandlePreeditChanged,
                        const gchar*);
 #endif
+  // Undo/redo operations won't trigger "begin-user-action" and
+  // "end-user-action" signals, so we need to hook into "undo" and "redo"
+  // signals and call OnBeforePossibleChange()/OnAfterPossibleChange() by
+  // ourselves.
+  CHROMEGTK_CALLBACK_0(AutocompleteEditViewGtk, void, HandleUndoRedo);
+  CHROMEGTK_CALLBACK_0(AutocompleteEditViewGtk, void, HandleUndoRedoAfter);
 
   CHROMEG_CALLBACK_1(AutocompleteEditViewGtk, void, HandleWindowSetFocus,
                      GtkWindow*, GtkWidget*);
@@ -269,10 +279,7 @@ class AutocompleteEditViewGtk : public AutocompleteEditView,
                           GtkTextIter* iter_max);
 
   // Return the number of characers in the current buffer.
-  int GetTextLength();
-
-  // Get the string contents for the given buffer.
-  std::wstring GetTextFromBuffer(GtkTextBuffer* buffer) const;
+  int GetTextLength() const;
 
   // Try to parse the current text as a URL and colorize the components.
   void EmphasizeURLComponents();
@@ -306,6 +313,18 @@ class AutocompleteEditViewGtk : public AutocompleteEditView,
   // If the selected text parses as a URL OwnPrimarySelection is invoked.
   void UpdatePrimarySelectionIfValidURL();
 
+  // Retrieves the first and last iterators in the |text_buffer_|, but excludes
+  // the anchor holding the |instant_view_| widget.
+  void GetTextBufferBounds(GtkTextIter* start, GtkTextIter* end) const;
+
+  // Validates an iterator in the |text_buffer_|, to make sure it doesn't go
+  // beyond the anchor for holding the |instant_view_| widget.
+  void ValidateTextBufferIter(GtkTextIter* iter) const;
+
+  // Adjusts vertical alignment of the |instant_view_| in the |text_view_|, to
+  // make sure they have the same baseline.
+  void AdjustVerticalAlignmentOfInstantView();
+
   // The widget we expose, used for vertically centering the real text edit,
   // since the height will change based on the font / font size, etc.
   OwnedWidgetGtk alignment_;
@@ -321,9 +340,16 @@ class AutocompleteEditViewGtk : public AutocompleteEditView,
   GtkTextTag* normal_text_tag_;
 
   // Objects for the instant suggestion text view.
+  GtkTextTag* instant_anchor_tag_;
+
+  // A widget for displaying instant suggestion text. It'll be attached to a
+  // child anchor in the |text_buffer_| object.
   GtkWidget* instant_view_;
-  GtkTextBuffer* instant_buffer_;
-  GtkTextTag* instant_text_tag_;
+
+  // A mark to split the content and the instant anchor. Wherever the end
+  // iterator of the text buffer is required, the iterator to this mark should
+  // be used.
+  GtkTextMark* instant_mark_;
 
   scoped_ptr<AutocompleteEditModel> model_;
   scoped_ptr<AutocompletePopupView> popup_view_;
@@ -434,7 +460,7 @@ class AutocompleteEditViewGtk : public AutocompleteEditView,
   // is not suggested text, that means the user manually made the selection.
   bool selection_suggested_;
 
-#if GTK_CHECK_VERSION(2,20,0)
+#if GTK_CHECK_VERSION(2, 20, 0)
   // Stores the text being composed by the input method.
   std::wstring preedit_;
 #endif