Fix default search box colors.

Bug: 1134721
Change-Id: I50136df0e71e647e4f6629457da13104a7431422
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2473140Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Yulun Wu <yulunwu@chromium.org>
Commit-Queue: Yulun Wu <yulunwu@chromium.org>
Auto-Submit: Yulun Wu <yulunwu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817339}

ash/app_list/app_list_color_provider_impl.cc

@@ -52,7 +52,7 @@ SkColor AppListColorProviderImpl::GetSearchBoxCardBackgroundColor() const {
 SkColor AppListColorProviderImpl::GetSearchBoxPlaceholderTextColor() const {
   return DeprecatedGetContentLayerColor(
       AshColorProvider::ContentLayerType::kTextColorSecondary,
-      /*default_color*/ gfx::kGoogleGrey200);
+      /*default_color*/ SkColorSetARGB(0xDE, 0x00, 0x00, 0x00));
 }
 
 SkColor AppListColorProviderImpl::GetSearchBoxTextColor(