Remove the WM_SYSCOMMAND handling from the LegacyRenderWidgetHostHWND class.

This handler was added to forward the message to the parent window for cases where the size of the
parent and the LegacyRenderWidgetHostHWND window were the same.

We can directly call DefWindowProc on the parent window for non client mouse messages which generates
WM_SYSCOMMAND for the parent window.

This simplifies the LegacyRenderWidgetHostHWND class and also fixes bugs with WM_SYSCOMMAND messages not
getting generated correctly due to missing styles on the LegacyRenderWidgetHostHWND hwnd which does not have
the same styles as the parent.

BUG=377367

Review URL: https://codereview.chromium.org/374283002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282248 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/legacy_render_widget_host_win.cc

@@ -224,6 +224,15 @@ LRESULT LegacyRenderWidgetHostHWND::OnMouseRange(UINT message,
     ret = GetWindowEventTarget(GetParent())->HandleMouseMessage(
         message, w_param, l_param, &msg_handled);
     handled = msg_handled;
+    // If the parent did not handle non client mouse messages, we call
+    // DefWindowProc on the message with the parent window handle. This
+    // ensures that WM_SYSCOMMAND is generated for the parent and we are
+    // out of the picture.
+    if (!handled &&
+         (message >= WM_NCMOUSEMOVE && message <= WM_NCXBUTTONDBLCLK)) {
+      ret = ::DefWindowProc(GetParent(), message, w_param, l_param);
+      handled = TRUE;
+    }
   }
   return ret;
 }
@@ -362,18 +371,4 @@ LRESULT LegacyRenderWidgetHostHWND::OnSize(UINT message,
   return 0;
 }
 
-LRESULT LegacyRenderWidgetHostHWND::OnSysCommand(UINT message,
-                                                 WPARAM w_param,
-                                                 LPARAM l_param) {
-  LRESULT ret = 0;
-  if (GetWindowEventTarget(GetParent())) {
-    bool msg_handled = false;
-    ret = GetWindowEventTarget(
-        GetParent())->HandleSysCommand(message, w_param, l_param,
-                                       &msg_handled);
-    SetMsgHandled(msg_handled);
-  }
-  return ret;
-}
-
 }  // namespace content

content/browser/renderer_host/legacy_render_widget_host_win.h

@@ -83,7 +83,6 @@ class CONTENT_EXPORT LegacyRenderWidgetHostHWND
                           OnMouseRange)
     MESSAGE_HANDLER_EX(WM_NCCALCSIZE, OnNCCalcSize)
     MESSAGE_HANDLER_EX(WM_SIZE, OnSize)
-    MESSAGE_HANDLER_EX(WM_SYSCOMMAND, OnSysCommand)
   END_MSG_MAP()
 
   HWND hwnd() { return m_hWnd; }

ui/base/win/window_event_target.h

@@ -74,17 +74,6 @@ class UI_BASE_EXPORT WindowEventTarget {
                                          WPARAM w_param,
                                          LPARAM l_param,
                                          bool* handled) = 0;
-
-  // Handles the WM_SYSCOMMAND message
-  // The |message| parameter identifies the message.
-  // The |w_param| and |l_param| values are as per MSDN docs.
-  // The |handled| parameter is an output parameter which when set to false
-  // indicates that the message should be DefProc'ed.
-  // Returns the result of processing the message.
-  virtual LRESULT HandleSysCommand(unsigned int message,
-                                   WPARAM w_param,
-                                   LPARAM l_param,
-                                   bool* handled) = 0;
  protected:
   WindowEventTarget();
   virtual ~WindowEventTarget();

ui/views/win/hwnd_message_handler.cc

@@ -981,16 +981,6 @@ LRESULT HWNDMessageHandler::HandleNcHitTestMessage(unsigned int message,
   return ret;
 }
 
-LRESULT HWNDMessageHandler::HandleSysCommand(unsigned int message,
-                                             WPARAM w_param,
-                                             LPARAM l_param,
-                                             bool* handled) {
-  OnSysCommand(static_cast<UINT>(w_param),
-               gfx::Point(CR_GET_X_LPARAM(l_param), CR_GET_Y_LPARAM(l_param)));
-  *handled = IsMsgHandled();
-  return 0;
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // HWNDMessageHandler, private:
 

ui/views/win/hwnd_message_handler.h

@@ -239,11 +239,6 @@ class VIEWS_EXPORT HWNDMessageHandler :
                                          LPARAM l_param,
                                          bool* handled) OVERRIDE;
 
-  virtual LRESULT HandleSysCommand(unsigned int message,
-                                   WPARAM w_param,
-                                   LPARAM l_param,
-                                   bool* handled);
-
   // Returns the auto-hide edges of the appbar. See
   // ViewsDelegate::GetAppbarAutohideEdges() for details. If the edges change,
   // OnAppbarAutohideEdgesChanged() is called.