Make some updates to BM bar for MD.

chrome/browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc

Index: chrome/browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc
diff --git a/chrome/browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc b/chrome/browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc
index 7c5787ba8f851eb515c1e5429bb98fd9bc9a8274..df00c88b85e611a28c087e84c1377dcaa7941e72 100644
--- a/chrome/browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc
+++ b/chrome/browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc
@@ -13,14 +13,22 @@
 #include "chrome/grit/generated_resources.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/l10n/l10n_util.h"
+#include "ui/base/resource/material_design/material_design_controller.h"
 #include "ui/base/theme_provider.h"
+#include "ui/native_theme/native_theme.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/controls/link.h"
 
 namespace {
 
 // Horizontal padding, in pixels, between the link and label.
-const int kViewPadding = 6;
+const int GetViewPadding() {
+  if (ui::MaterialDesignController::IsModeMaterial())
+    return views::Label(base::ASCIIToUTF16(" ")).GetPreferredSize().width();

[sky, 2015/10/26 23:56:38]

Can we cache this? We don't really support changing the fonts on the fly.

[Evan Stade, 2015/10/27 17:05:42]

hmm, you're right. I thought we did support live font size changes but it
appears not. Done.

+
+  // Pre-MD is hard-coded to 6px.
+  return 6;
+}
 
 }  // namespace
 
@@ -34,6 +42,7 @@ BookmarkBarInstructionsView::BookmarkBarInstructionsView(
   instructions_ = new views::Label(
       l10n_util::GetStringUTF16(IDS_BOOKMARKS_NO_ITEMS));
   instructions_->SetAutoColorReadabilityEnabled(false);
+  instructions_->SetHorizontalAlignment(gfx::ALIGN_LEFT);

[Evan Stade, 2015/10/22 21:52:12]

the left align here and below fixes some jiggling that occurs when you resize
the browser window (the horizontal alignment of the text changes slightly as the
point of elision changes and the label is on the default center alignment).

   AddChildView(instructions_);
 
   if (browser_defaults::kShowImportOnBookmarkBar) {
@@ -44,6 +53,7 @@ BookmarkBarInstructionsView::BookmarkBarInstructionsView(
     import_link_->set_listener(this);
     import_link_->set_context_menu_controller(this);
     import_link_->SetAutoColorReadabilityEnabled(false);
+    import_link_->SetHorizontalAlignment(gfx::ALIGN_LEFT);
     AddChildView(import_link_);
   }
 }
@@ -62,7 +72,7 @@ gfx::Size BookmarkBarInstructionsView::GetPreferredSize() const {
     }
     width += pref.width();
   }
-  width += (child_count() - 1) * kViewPadding;
+  width += (child_count() - 1) * GetViewPadding();
   if (ascent != 0)
     height = std::max(ascent + descent, height);
   return gfx::Size(width, height);
@@ -82,7 +92,7 @@ void BookmarkBarInstructionsView::Layout() {
       y = (height() - pref.height()) / 2;
     int view_width = std::min(remaining_width, pref.width());
     view->SetBounds(x, y, view_width, pref.height());
-    x += view_width + kViewPadding;
+    x += view_width + GetViewPadding();
     remaining_width = std::max(0, width() - x);
   }
 }
@@ -128,6 +138,23 @@ void BookmarkBarInstructionsView::UpdateColors() {
   SkColor text_color =
       theme_provider->GetColor(ThemeProperties::COLOR_BOOKMARK_TEXT);
   instructions_->SetEnabledColor(text_color);
-  if (import_link_)
+  if (!import_link_)
+    return;
+
+  if (!ui::MaterialDesignController::IsModeMaterial()) {
     import_link_->SetEnabledColor(text_color);
+  } else {
+    // For MD, use the default link color if it provides enough contrast. If
+    // contrast is too low, fall back to the bookmark text color and use an
+    // underline to make it obvious it's a link. The default color readability
+    // code (which only adjusts luminance) doesn't work well in this case.
+    SkColor bg = theme_provider->GetColor(
+        ThemeProperties::ThemeProperties::COLOR_TOOLBAR);
+    SkColor link_color =
+        GetNativeTheme()->GetSystemColor(ui::NativeTheme::kColorId_LinkEnabled);
+    bool link_has_contrast = color_utils::GetContrastRatio(link_color, bg) >=
+                             color_utils::kMinimumReadableContrastRatio;
+    import_link_->SetUnderline(!link_has_contrast);
+    import_link_->SetEnabledColor(link_has_contrast ? link_color : text_color);
+  }
 }