backout previous check-in because the tree is closed

widget/src/windows/nsWindow.cpp

@@ -3233,7 +3233,7 @@ UINT nsWindow::MapFromNativeToDOM(UINT aNativeKeyCode)
 {
   switch (aNativeKeyCode) {
     case VK_OEM_1:     return NS_VK_SEMICOLON;     // 0xBA, For the US standard keyboard, the ';:' key
-    case VK_OEM_PLUS:  return NS_VK_ADD;           // 0xBB, For any country/region, the '+' key
+    case VK_OEM_PLUS:  return NS_VK_EQUALS;        // 0xBB, For any country/region, the '+' key
     case VK_OEM_MINUS: return NS_VK_SUBTRACT;      // 0xBD, For any country/region, the '-' key
   }
 
@@ -3341,11 +3341,13 @@ BOOL nsWindow::OnKeyDown(UINT aVirtualKeyCode, UINT aScanCode, LPARAM aKeyData)
   BOOL gotMsg = ::PeekMessageW(&msg, mWnd, WM_KEYFIRST, WM_KEYLAST, PM_NOREMOVE | PM_NOYIELD);
   // Enter and backspace are always handled here to avoid for example the
   // confusion between ctrl-enter and ctrl-J.
-  // Ctrl+[Add, Subtract] are always handled here to make text zoom shortcuts work
-  // on different keyboard layouts.
+  // Ctrl+[Add, Subtract, Equals] are always handled here to make text zoom shortcuts work
+  // on different keyboard layouts (Equals is needed because many layouts return it when
+  // pressing Ctrl++ and that's why it's also accepted as a shortcut for increasing zoom).
   if (virtualKeyCode == NS_VK_RETURN || virtualKeyCode == NS_VK_BACK ||
       (mIsControlDown && !mIsAltDown && !mIsShiftDown &&
-       (virtualKeyCode == NS_VK_ADD || virtualKeyCode == NS_VK_SUBTRACT)) ||
+       (virtualKeyCode == NS_VK_ADD || virtualKeyCode == NS_VK_SUBTRACT ||
+        virtualKeyCode == NS_VK_EQUALS)) ||
       ((mIsControlDown || mIsAltDown) && KeyboardLayout::IsPrintableCharKey (aVirtualKeyCode)))
   {
     // Remove a possible WM_CHAR or WM_SYSCHAR messages from the message queue.