update the size and clickable area of extension icon in Chormium fork version 88?

I have got a Chromium fork of version 88, and i have changed the size of extension icon from 28*28 to 68*68, but the clickable area of icon was still below the bottom half of the whole icon area, It meams that you can only hit the bottom half of the icon to show the popul.html by the mouse.

I have modified the file "chromium\src\chrome\browser\ui\layout_constants.cc" to make the icon size changed,

    case TOOLBAR_BUTTON_HEIGHT:
      // return touch_ui ? 48 : 28;
      return touch_ui ? 48 : 68;
    case TOOLBAR_ELEMENT_PADDING:
      return touch_ui ? 0 : 3;
      // return touch_ui ? 0 : 4;

So which files should i edit to make the click works?