Interpret '?' and Ctrl-K or Ctrl-E as putting omnibox in keyword search mode for Default Search Pro…

components/omnibox/browser/omnibox_edit_model.h

Index: components/omnibox/browser/omnibox_edit_model.h
diff --git a/components/omnibox/browser/omnibox_edit_model.h b/components/omnibox/browser/omnibox_edit_model.h
index de6ff02da4bedd70185ef080522c523a1a475c2d..be3d952728ed3e16112fad1cefa332f3b5befe9c 100644
--- a/components/omnibox/browser/omnibox_edit_model.h
+++ b/components/omnibox/browser/omnibox_edit_model.h
@@ -37,11 +37,13 @@ class Rect;
 
 // Reasons why the Omnibox could change into keyword mode.
 // These numeric values are used in UMA logs; do not change them.
-enum EnteredKeywordModeMethod {
-  ENTERED_KEYWORD_MODE_VIA_TAB = 0,
-  ENTERED_KEYWORD_MODE_VIA_SPACE_AT_END = 1,
-  ENTERED_KEYWORD_MODE_VIA_SPACE_IN_MIDDLE = 2,
-  ENTERED_KEYWORD_MODE_NUM_ITEMS
+enum class KeywordModeEntryMethod {
+  TAB = 0,
+  SPACE_AT_END = 1,
+  SPACE_IN_MIDDLE = 2,
+  KEYBOARD_SHORTCUT = 3,
+  QUESTION_MARK = 4,
+  NUM_ITEMS,
 };
 
 class OmniboxEditModel {
@@ -60,6 +62,7 @@ class OmniboxEditModel {
           const base::string16& gray_text,
           const base::string16& keyword,
           bool is_keyword_hint,
+          KeywordModeEntryMethod keyword_mode_entry_method,
           bool url_replacement_enabled,
           OmniboxFocusState focus_state,
           FocusSource focus_source,
@@ -72,6 +75,7 @@ class OmniboxEditModel {
     const base::string16 gray_text;
     const base::string16 keyword;
     const bool is_keyword_hint;
+    KeywordModeEntryMethod keyword_mode_entry_method;
     bool url_replacement_enabled;
     OmniboxFocusState focus_state;
     FocusSource focus_source;
@@ -237,10 +241,14 @@ class OmniboxEditModel {
   }
 
   // Accepts the current keyword hint as a keyword. It always returns true for
-  // caller convenience. |entered_method| indicates how the use entered
-  // keyword mode. This parameter is only used for metrics/logging; it's not
-  // used to change user-visible behavior.
-  bool AcceptKeyword(EnteredKeywordModeMethod entered_method);
+  // caller convenience. |entered_method| indicates how the user entered
+  // keyword mode.
+  bool AcceptKeyword(KeywordModeEntryMethod entry_method);
+
+  // Sets the current keyword to that of the user's default search provider and
+  // updates the view so the user sees the keyword chip in the omnibox.
+  void EnterKeywordModeForDefaultSearchProvider(
+      KeywordModeEntryMethod entry_method);
 
   // Accepts the current temporary text as the user text.
   void AcceptTemporaryTextAsUserText();
@@ -336,6 +344,7 @@ class OmniboxEditModel {
                              size_t selection_end,
                              bool selection_differs,
                              bool text_differs,
+                             bool keyword_differs,
                              bool just_deleted_text,
                              bool allow_keyword_ui_change);
 
@@ -547,6 +556,11 @@ class OmniboxEditModel {
   // keyword_ to show a "Press <tab> to search" sort of hint.
   bool is_keyword_hint_;
 
+  // Indicates how the user entered keyword mode if the user is actually in
+  // keyword mode.  Otherwise, the value of this variable is undefined.  This
+  // is used to restore the user's search terms upon a call to ClearKeyword().
+  KeywordModeEntryMethod keyword_mode_entry_method_;
+
   // This is needed to properly update the SearchModel state when the user
   // presses escape.
   bool in_revert_;