Change the Frame Calculation to Use GetSystemMetricsForHwnd

SM_CXSIZEFRAME from GetSystemMetrics is based off of the primary monitor's DPI.
GetSystemMetricsForHwnd accounts for the system metrics taking into account the
DPI of the HWND.

BUG=426656

Review-Url: https://codereview.chromium.org/2110323002
Cr-Commit-Position: refs/heads/master@{#403326}

chrome/browser/ui/views/frame/browser_desktop_window_tree_host_win.cc

@@ -94,7 +94,9 @@ bool BrowserDesktopWindowTreeHostWin::GetClientAreaInsets(
     // In fullscreen mode there is no frame.
     *insets = gfx::Insets();
   } else {
-    const int frame_thickness = GetSystemMetrics(SM_CXSIZEFRAME);
+    const int frame_thickness =
+        display::win::ScreenWin::GetSystemMetricsForHwnd(
+            GetHWND(), SM_CXSIZEFRAME);
     // Reduce the Windows non-client border size because we extend the border
     // into our client area in UpdateDWMFrame().
     *insets = gfx::Insets(0, frame_thickness, frame_thickness,