Significantly increase contrast for inactive tabs

This changes tab text color from ~GG200 and GG700 to white and GG800
which makes inactive tabs in both incognito and default theme easier to
read. It's especially important for themed-frame windows though where
very light grey on white provided significantly worse contrast.

This also increases tab-separator opacity to better match the increased
contrast.

Bug: chromium:855091
Change-Id: I0ec7208d6b1158e4abbb361acd119d3a48020f10
Reviewed-on: https://chromium-review.googlesource.com/1109271
Commit-Queue: Peter Boström <pbos@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569343}

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

@@ -104,8 +104,11 @@ SkColor BrowserNonClientFrameView::GetToolbarTopSeparatorColor() const {
 
 SkColor BrowserNonClientFrameView::GetTabSeparatorColor() const {
   DCHECK(MD::IsRefreshUi());
-  constexpr SkAlpha kTabSeparatorAlpha = 0x59;  // 35%
-  return GetContrastingColorAgainstFrame(kTabSeparatorAlpha);
+  constexpr SkAlpha kTabSeparatorAlpha = 0x6E;  // 43%
+  const SkColor frame_color = GetFrameColor();
+  const SkColor base_color =
+      color_utils::BlendTowardOppositeLuma(frame_color, SK_AlphaOPAQUE);
+  return color_utils::AlphaBlend(base_color, frame_color, kTabSeparatorAlpha);
 }
 
 SkColor BrowserNonClientFrameView::GetTabBackgroundColor(TabState state) const {
@@ -118,8 +121,11 @@ SkColor BrowserNonClientFrameView::GetTabBackgroundColor(TabState state) const {
 }
 
 SkColor BrowserNonClientFrameView::GetTabForegroundColor(TabState state) const {
-  if (MD::IsRefreshUi() && state == TAB_INACTIVE && ShouldPaintAsThemed())
-    return GetContrastingColorAgainstFrame(gfx::kGoogleGreyAlpha700);
+  if (MD::IsRefreshUi() && state == TAB_INACTIVE && ShouldPaintAsThemed()) {
+    return color_utils::IsDark(GetFrameColor()) ? SK_ColorWHITE
+                                                : gfx::kGoogleGrey800;
+  }
+
   const auto color_id = state == TAB_ACTIVE
                             ? ThemeProperties::COLOR_TAB_TEXT
                             : ThemeProperties::COLOR_BACKGROUND_TAB_TEXT;
@@ -552,11 +558,3 @@ SkColor BrowserNonClientFrameView::GetThemeOrDefaultColor(int color_id) const {
                                : ThemeProperties::GetDefaultColor(
                                      color_id, browser_view_->IsIncognito());
 }
-
-SkColor BrowserNonClientFrameView::GetContrastingColorAgainstFrame(
-    SkAlpha alpha) const {
-  const SkColor frame_color = GetFrameColor();
-  const SkColor base_color =
-      color_utils::BlendTowardOppositeLuma(frame_color, SK_AlphaOPAQUE);
-  return color_utils::AlphaBlend(base_color, frame_color, alpha);
-}

chrome/browser/ui/views/frame/browser_non_client_frame_view.h

@@ -189,9 +189,6 @@ class BrowserNonClientFrameView : public views::NonClientFrameView,
   // default theme properties.
   SkColor GetThemeOrDefaultColor(int color_id) const;
 
-  // Returns a color that contrasts well with the frame.
-  SkColor GetContrastingColorAgainstFrame(SkAlpha alpha) const;
-
   // The frame that hosts this view.
   BrowserFrame* frame_;
 

chrome/browser/ui/views/tabs/new_tab_button.cc

@@ -21,6 +21,7 @@
 #include "third_party/skia/include/pathops/SkPathOps.h"
 #include "ui/base/default_theme_provider.h"
 #include "ui/base/material_design/material_design_controller.h"
+#include "ui/gfx/color_palette.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/paint_vector_icon.h"
 #include "ui/gfx/scoped_canvas.h"
@@ -28,7 +29,6 @@
 #include "ui/views/animation/ink_drop_impl.h"
 #include "ui/views/animation/ink_drop_mask.h"
 #include "ui/views/widget/widget.h"
-
 #if defined(OS_WIN)
 #include "ui/display/win/screen_win.h"
 #include "ui/gfx/win/hwnd_util.h"
@@ -518,7 +518,10 @@ SkColor NewTabButton::GetButtonFillColor() const {
 
 void NewTabButton::InitButtonIcons() {
   DCHECK(MD::IsNewerMaterialUi());
-  const SkColor icon_color = tab_strip_->GetTabForegroundColor(TAB_INACTIVE);
+  const SkColor icon_color =
+      color_utils::IsDark(tab_strip_->GetTabForegroundColor(TAB_INACTIVE))
+          ? gfx::kChromeIconGrey
+          : SK_ColorWHITE;
   // TODO(b/851041): is there a better source for these icon sizes?
   const int size = MD::IsTouchOptimizedUiEnabled() ? 14 : 12;
   plus_icon_ = gfx::CreateVectorIcon(kNewTabButtonPlusIcon, size, icon_color);