Change the default color and opacity of AppListView

Test: None
Bug: 934344
Change-Id: Ia0ce9b0428f8cff1fca654ee076303402f49bb74
Reviewed-on: https://chromium-review.googlesource.com/c/1487871Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Commit-Queue: Andrew Xu <andrewxu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#635597}

ash/app_list/app_list_presenter_delegate_unittest.cc

@@ -1279,7 +1279,7 @@ TEST_F(AppListPresenterDelegateHomeLauncherTest, BackgroundOpacity) {
 
   // The opacity should be set on the color, not the layer. Setting opacity on
   // the layer will change the opacity of the blur effect, which is not desired.
-  const U8CPU clamshell_background_opacity = static_cast<U8CPU>(255 * 0.7);
+  const U8CPU clamshell_background_opacity = static_cast<U8CPU>(255 * 0.74);
   EXPECT_EQ(SkColorSetA(app_list::AppListView::kDefaultBackgroundColor,
                         clamshell_background_opacity),
             GetAppListView()->GetAppListBackgroundShieldColorForTest());

ash/app_list/views/app_list_view.h

@@ -74,13 +74,13 @@ class APP_LIST_EXPORT AppListView : public views::WidgetDelegateView {
   static constexpr float kAppListOpacity = 0.95;
 
   // The opacity of the app list background with blur.
-  static constexpr float kAppListOpacityWithBlur = 0.7;
+  static constexpr float kAppListOpacityWithBlur = 0.74;
 
   // The preferred blend alpha with wallpaper color for background.
   static constexpr int kAppListColorDarkenAlpha = 178;
 
   // The defualt color of the app list background.
-  static constexpr SkColor kDefaultBackgroundColor = SK_ColorBLACK;
+  static constexpr SkColor kDefaultBackgroundColor = gfx::kGoogleGrey900;
 
   // The duration the AppListView ignores scroll events which could transition
   // its state.