Fix the black patch which would appear at the top of app windows in Chrome desktop windows with HiD…

chrome/browser/ui/views/apps/app_window_desktop_window_tree_host_win.cc

Index: chrome/browser/ui/views/apps/app_window_desktop_window_tree_host_win.cc
diff --git a/chrome/browser/ui/views/apps/app_window_desktop_window_tree_host_win.cc b/chrome/browser/ui/views/apps/app_window_desktop_window_tree_host_win.cc
index b2301e69bcfb06ec07e0dd16cf907c8173bb12e1..b14d3c07d621c34f75618ed3bb9b96ea0f625f15 100644
--- a/chrome/browser/ui/views/apps/app_window_desktop_window_tree_host_win.cc
+++ b/chrome/browser/ui/views/apps/app_window_desktop_window_tree_host_win.cc
@@ -72,11 +72,19 @@ void AppWindowDesktopWindowTreeHostWin::UpdateDWMFrame() {
   // If the opaque frame is visible, we use the default (zero) margins.
   // Otherwise, we need to figure out how to extend the glass in.
   if (app_window_->glass_frame_view()) {
-    gfx::Insets insets = app_window_->glass_frame_view()->GetGlassInsets();
-    margins.cxLeftWidth = insets.left();
-    margins.cxRightWidth = insets.right();
-    margins.cyBottomHeight = insets.bottom();
-    margins.cyTopHeight = insets.top();
+    gfx::Insets insets_in_dip =
+        app_window_->glass_frame_view()->GetGlassInsetsInDIP();
+    // The DWM API's expect values in pixels. We need to convert from DIP to
+    // pixels here.
+    gfx::Rect insets_rect(insets_in_dip.left(),
+                          insets_in_dip.top(),
+                          insets_in_dip.right() - insets_in_dip.left(),
+                          insets_in_dip.bottom() - insets_in_dip.top());
+    insets_rect = gfx::win::DIPToScreenRect(insets_rect);
+    margins.cxLeftWidth = insets_rect.x();
+    margins.cxRightWidth = insets_rect.x() + insets_rect.width();
+    margins.cyBottomHeight = insets_rect.y() + insets_rect.height();
+    margins.cyTopHeight = insets_rect.y();
   }
 
   DwmExtendFrameIntoClientArea(GetHWND(), &margins);