Break up some 'magic' numbers in ZcrRemoteShellTest

Also some slight refactoring.

Bug: 997768
Change-Id: I25c6f2815c12b6de5c737fd9f6831149a92b7675
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1783663Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#693857}

components/exo/wayland/zcr_remote_shell.cc

@@ -1224,8 +1224,6 @@ gfx::Insets GetWorkAreaInsetsInClientPixel(
     float default_dsf,
     const gfx::Size& size_in_client_pixel,
     const gfx::Rect& work_area_in_dp) {
-  gfx::Rect work_area_in_display = display.work_area();
-  work_area_in_display.Offset(-display.bounds().x(), -display.bounds().y());
   gfx::Rect local_work_area_in_dp = work_area_in_dp;
   local_work_area_in_dp.Offset(-display.bounds().x(), -display.bounds().y());
   gfx::Rect work_area_in_client_pixel = ScaleBoundsToPixelSnappedToParent(

components/exo/wayland/zcr_remote_shell_unittest.cc

@@ -16,17 +16,21 @@ using ZcrRemoteShellTest = test::ExoTestBase;
 
 TEST_F(ZcrRemoteShellTest, GetWorkAreaInsetsInClientPixel) {
   UpdateDisplay("3000x2000*2.25,1920x1080");
+
   auto display = display::Screen::GetScreen()->GetPrimaryDisplay();
+  const float device_scale_factor = display.device_scale_factor();
+  EXPECT_EQ(2.25f, device_scale_factor);
   gfx::Insets insets = wayland::GetWorkAreaInsetsInClientPixel(
-      display, 2.25f, gfx::Size(3000, 2000), display.work_area());
-  EXPECT_EQ(gfx::Insets(0, 0, 128, 0), insets);
+      display, device_scale_factor, display.GetSizeInPixel(),
+      display.work_area());
+  EXPECT_EQ(gfx::Insets(0, 0, 128, 0).ToString(), insets.ToString());
 
   auto secondary_display = GetSecondaryDisplay();
-  gfx::Size secondary_size(1920, 1080);
+  gfx::Size secondary_size(secondary_display.size());
   gfx::Size secondary_size_in_client_pixel =
-      gfx::ScaleToRoundedSize(secondary_size, 2.25f);
+      gfx::ScaleToRoundedSize(secondary_size, device_scale_factor);
   gfx::Insets secondary_insets = wayland::GetWorkAreaInsetsInClientPixel(
-      secondary_display, 2.25f, secondary_size_in_client_pixel,
+      secondary_display, device_scale_factor, secondary_size_in_client_pixel,
       secondary_display.work_area());
   EXPECT_EQ(gfx::Insets(0, 0, 126, 0).ToString(), secondary_insets.ToString());
 
@@ -36,11 +40,11 @@ TEST_F(ZcrRemoteShellTest, GetWorkAreaInsetsInClientPixel) {
   display = display::Screen::GetScreen()->GetPrimaryDisplay();
   ASSERT_EQ(display.bounds(), display.work_area());
   gfx::Insets stable_insets = wayland::GetWorkAreaInsetsInClientPixel(
-      display, 2.25f, gfx::Size(3000, 2000),
+      display, device_scale_factor, display.GetSizeInPixel(),
       wayland::GetStableWorkArea(display));
   EXPECT_EQ(gfx::Insets(0, 0, 128, 0).ToString(), stable_insets.ToString());
   gfx::Insets secondary_stable_insets = wayland::GetWorkAreaInsetsInClientPixel(
-      secondary_display, 2.25f, secondary_size_in_client_pixel,
+      secondary_display, device_scale_factor, secondary_size_in_client_pixel,
       wayland::GetStableWorkArea(secondary_display));
   EXPECT_EQ(gfx::Insets(0, 0, 126, 0).ToString(),
             secondary_stable_insets.ToString());