Revert of Support finer grained font weights on Mac. (patchset #6 id:240001 of...

Revert of Support finer grained font weights on Mac. (patchset #6 id:240001 of https://codereview.chromium.org/2869803005/ )

Reason for revert:
Need to test 10.11 again.

failures in the build cycle at https://luci-milo.appspot.com/buildbot/chromium.mac/Mac10.11%20Tests/12666

Original issue's description:
> Support finer grained font weights on Mac.
>
> We want to explore a MEDIUM weight for button text under Harmony. This
> is consistent with MD and helps compensate for buttons not using solid
> black for the font color.
>
> The San Francisco font in 10.11 and 10.12 has good support for finer
> grained weights and is the font Chrome UI is mostly concerned with, so
> focus testing on that but survey expectations for all supported OS
> versions.
>
> BUG=691891
>
> Review-Url: https://codereview.chromium.org/2869803005
> Cr-Commit-Position: refs/heads/master@{#473457}
> Committed: https://chromium.googlesource.com/chromium/src/+/bc62dfeaf37c83a79f393cb536fb22b39ea87097

TBR=asvitkine@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=691891

Review-Url: https://codereview.chromium.org/2898613002
Cr-Commit-Position: refs/heads/master@{#473460}

ui/gfx/platform_font_mac.mm

@@ -8,9 +8,7 @@
 
 #include <Cocoa/Cocoa.h>
 
-#import "base/mac/foundation_util.h"
-#include "base/mac/scoped_cftyperef.h"
-#import "base/mac/scoped_nsobject.h"
+#include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/gfx/canvas.h"
@@ -21,60 +19,6 @@ namespace gfx {
 
 namespace {
 
-// How to get from NORMAL weight to a fine-grained font weight using calls to
-// -[NSFontManager convertWeight:(BOOL)upFlag ofFont:(NSFont)].
-struct WeightSolver {
-  int steps_up;    // Times to call with upFlag:YES.
-  int steps_down;  // Times to call with upFlag:NO.
-  // Either NORMAL or BOLD: whether to set the NSBoldFontMask symbolic trait.
-  Font::Weight nearest;
-};
-
-// Solve changes to the font weight according to the following table, from
-// https://developer.apple.com/reference/appkit/nsfontmanager/1462321-convertweight
-// 1. ultralight                     | none
-// 2. thin                           | W1. ultralight
-// 3. light, extralight              | W2. extralight
-// 4. book                           | W3. light
-// 5. regular, plain, display, roman | W4. semilight
-// 6. medium                         | W5. medium
-// 7. demi, demibold                 | none
-// 8. semi, semibold                 | W6. semibold
-// 9. bold                           | W7. bold
-// 10. extra, extrabold              | W8. extrabold
-// 11. heavy, heavyface              | none
-// 12. black, super                  | W9. ultrabold
-// 13. ultra, ultrablack, fat        | none
-// 14. extrablack, obese, nord       | none
-WeightSolver WeightChangeFromNormal(Font::Weight desired) {
-  using Weight = Font::Weight;
-  switch (desired) {
-    case Weight::THIN:
-      // It's weird, but to get LIGHT and THIN fonts, first go up a step.
-      // Without this, the font stays stuck at NORMAL. See
-      // PlatformFontMacTest, FontWeightAPIConsistency.
-      return {1, 3, Weight::NORMAL};
-    case Weight::EXTRA_LIGHT:
-      return {1, 2, Weight::NORMAL};
-    case Weight::LIGHT:
-      return {1, 1, Weight::NORMAL};
-    case Weight::NORMAL:
-      return {0, 0, Weight::NORMAL};
-    case Weight::MEDIUM:
-      return {1, 0, Weight::NORMAL};
-    case Weight::SEMIBOLD:
-      return {0, 1, Weight::BOLD};
-    case Weight::BOLD:
-      return {0, 0, Weight::BOLD};
-    case Weight::EXTRA_BOLD:
-      return {1, 0, Weight::BOLD};
-    case Weight::BLACK:
-      return {3, 0, Weight::BOLD};  // Skip row 12.
-    case Weight::INVALID:
-      return {0, 0, Weight::NORMAL};
-  }
-}
-
 // Returns the font style for |font|. Disregards Font::UNDERLINE, since NSFont
 // does not support it as a trait.
 int GetFontStyleFromNSFont(NSFont* font) {
@@ -87,56 +31,8 @@ int GetFontStyleFromNSFont(NSFont* font) {
 
 // Returns the Font weight for |font|.
 Font::Weight GetFontWeightFromNSFont(NSFont* font) {
-  if (!font)
-    return Font::Weight::INVALID;
-
-  // Map CoreText weights in a manner similar to ct_weight_to_fontstyle() from
-  // SkFontHost_mac.cpp, but adjust for MEDIUM so that the San Francisco's
-  // custom MEDIUM weight can be picked out. San Francisco has weights:
-  // [0.23, 0.23, 0.3, 0.4, 0.56, 0.62, 0.62, ...] (no thin weights).
-  // See PlatformFontMacTest.FontWeightAPIConsistency for details.
-  // Note that the table Skia uses is also determined by experiment.
-  constexpr struct {
-    CGFloat ct_weight;
-    Font::Weight gfx_weight;
-  } weight_map[] = {
-      // Missing: Apple "ultralight".
-      {-0.70, Font::Weight::THIN},
-      {-0.50, Font::Weight::EXTRA_LIGHT},
-      {-0.23, Font::Weight::LIGHT},
-      {0.00, Font::Weight::NORMAL},
-      {0.23, Font::Weight::MEDIUM},  // Note: adjusted from 0.20 vs Skia.
-      // Missing: Apple "demibold".
-      {0.30, Font::Weight::SEMIBOLD},
-      {0.40, Font::Weight::BOLD},
-      {0.60, Font::Weight::EXTRA_BOLD},
-      // Missing: Apple "heavyface".
-      // Values will be capped to BLACK (this entry is here for consistency).
-      {0.80, Font::Weight::BLACK},
-      // Missing: Apple "ultrablack".
-      // Missing: Apple "extrablack".
-  };
-  base::ScopedCFTypeRef<CFDictionaryRef> traits(
-      CTFontCopyTraits(base::mac::NSToCFCast(font)));
-  DCHECK(traits);
-  CFNumberRef cf_weight = base::mac::GetValueFromDictionary<CFNumberRef>(
-      traits, kCTFontWeightTrait);
-  // A missing weight attribute just means 0 -> NORMAL.
-  if (!cf_weight)
-    return Font::Weight::NORMAL;
-
-  // Documentation is vague about what sized floating point type should be used.
-  // However, numeric_limits::epsilon() for 64-bit types is too small to match
-  // the above table, so use 32-bit float.
-  float weight_value;
-  Boolean success =
-      CFNumberGetValue(cf_weight, kCFNumberFloatType, &weight_value);
-  DCHECK(success);
-  for (const auto& item : weight_map) {
-    if (weight_value - item.ct_weight <= std::numeric_limits<float>::epsilon())
-      return item.gfx_weight;
-  }
-  return Font::Weight::BLACK;
+  NSFontSymbolicTraits traits = [[font fontDescriptor] symbolicTraits];
+  return (traits & NSFontBoldTrait) ? Font::Weight::BOLD : Font::Weight::NORMAL;
 }
 
 // Returns an autoreleased NSFont created with the passed-in specifications.
@@ -204,43 +100,24 @@ Font PlatformFontMac::DeriveFont(int size_delta,
                                  Font::Weight weight) const {
   // For some reason, creating fonts using the NSFontDescriptor API's seem to be
   // unreliable. Hence use the NSFontManager.
-  NSFont* derived = native_font_;
+  NSFont* derived_font = native_font_;
   NSFontManager* font_manager = [NSFontManager sharedFontManager];
 
-  if (weight != font_weight_) {
-    // Find a font without any bold traits. Ideally, all bold traits are
-    // removed here, but non-symbolic traits are read-only properties of a
-    // particular set of glyphs. And attempting to "reset" the attribute with a
-    // new font descriptor will lose internal properties that Mac decorates its
-    // UI fonts with. E.g., solving the plans below from NORMAL result in a
-    // CTFontDescriptor attribute entry of NSCTFontUIUsageAttribute in
-    // CTFont{Regular,Medium,Demi,Emphasized,Heavy,Black}Usage. Attempting to
-    // "solve" weights starting at other than NORMAL has unpredictable results.
-    if (font_weight_ != Font::Weight::NORMAL)
-      derived = [font_manager convertFont:derived toHaveTrait:NSUnboldFontMask];
-    DLOG_IF(WARNING, GetFontWeightFromNSFont(derived) != Font::Weight::NORMAL)
-        << "Deriving from a font with an internal unmodifiable weight.";
-
-    WeightSolver plan = WeightChangeFromNormal(weight);
-    if (plan.nearest == Font::Weight::BOLD)
-      derived = [font_manager convertFont:derived toHaveTrait:NSBoldFontMask];
-    for (int i = 0; i < plan.steps_up; ++i)
-      derived = [font_manager convertWeight:YES ofFont:derived];
-    for (int i = 0; i < plan.steps_down; ++i)
-      derived = [font_manager convertWeight:NO ofFont:derived];
-  }
+  NSFontTraitMask bold_trait_mask =
+      weight >= Font::Weight::BOLD ? NSBoldFontMask : NSUnboldFontMask;
+  derived_font =
+      [font_manager convertFont:derived_font toHaveTrait:bold_trait_mask];
 
-  if (style != font_style_) {
-    NSFontTraitMask italic_trait_mask =
-        (style & Font::ITALIC) ? NSItalicFontMask : NSUnitalicFontMask;
-    derived = [font_manager convertFont:derived toHaveTrait:italic_trait_mask];
-  }
+  NSFontTraitMask italic_trait_mask =
+      (style & Font::ITALIC) ? NSItalicFontMask : NSUnitalicFontMask;
+  derived_font =
+      [font_manager convertFont:derived_font toHaveTrait:italic_trait_mask];
 
-  if (size_delta != 0)
-    derived = [font_manager convertFont:derived toSize:font_size_ + size_delta];
+  derived_font =
+      [font_manager convertFont:derived_font toSize:font_size_ + size_delta];
 
-  return Font(new PlatformFontMac(derived, font_name_, font_size_ + size_delta,
-                                  style, weight));
+  return Font(new PlatformFontMac(derived_font, font_name_,
+                                  font_size_ + size_delta, style, weight));
 }
 
 int PlatformFontMac::GetHeight() {

ui/views/examples/example_combobox_model.cc

@@ -9,9 +9,9 @@
 namespace views {
 namespace examples {
 
-ExampleComboboxModel::ExampleComboboxModel(const char* const* strings,
-                                           int count)
-    : strings_(strings), count_(count) {}
+ExampleComboboxModel::ExampleComboboxModel(const char** strings, int count)
+    : strings_(strings), count_(count) {
+}
 
 ExampleComboboxModel::~ExampleComboboxModel() {
 }

ui/views/examples/example_combobox_model.h

@@ -13,7 +13,7 @@ namespace examples {
 
 class ExampleComboboxModel : public ui::ComboboxModel {
  public:
-  ExampleComboboxModel(const char* const* strings, int count);
+  ExampleComboboxModel(const char** strings, int count);
   ~ExampleComboboxModel() override;
 
   // ui::ComboboxModel:
@@ -21,8 +21,8 @@ class ExampleComboboxModel : public ui::ComboboxModel {
   base::string16 GetItemAt(int index) override;
 
  private:
-  const char* const* const strings_;
-  const int count_;
+  const char** strings_;
+  int count_;
 
   DISALLOW_COPY_AND_ASSIGN(ExampleComboboxModel);
 };

ui/views/examples/text_example.cc

@@ -50,17 +50,6 @@ const char* kTextExamples[] = { "Short", "Long", "Ampersands", "RTL Hebrew", };
 const char* kElideBehaviors[] = { "Elide", "No Elide", "Fade", };
 const char* kPrefixOptions[] = { "Default", "Show", "Hide", };
 const char* kHorizontalAligments[] = { "Default", "Left", "Center", "Right", };
-constexpr const char* kWeightLabels[] = {
-    "Thin",     "Extra Light", "Light",      "Normal", "Medium",
-    "Semibold", "Bold",        "Extra Bold", "Black",
-};
-constexpr gfx::Font::Weight kFontWeights[]{
-    gfx::Font::Weight::THIN,   gfx::Font::Weight::EXTRA_LIGHT,
-    gfx::Font::Weight::LIGHT,  gfx::Font::Weight::NORMAL,
-    gfx::Font::Weight::MEDIUM, gfx::Font::Weight::SEMIBOLD,
-    gfx::Font::Weight::BOLD,   gfx::Font::Weight::EXTRA_BOLD,
-    gfx::Font::Weight::BLACK,
-};
 
 // Toggles bit |flag| on |flags| based on state of |checkbox|.
 void SetFlagFromCheckbox(Checkbox* checkbox, int* flags, int flag) {
@@ -98,24 +87,17 @@ class TextExample::TextExampleView : public View {
   void set_elide(gfx::ElideBehavior elide) { elide_ = elide; }
 
   int GetStyle() const { return font_list_.GetFontStyle(); }
-  void SetStyle(int style) {
-    base_font_ = base_font_.DeriveWithStyle(style);
-    font_list_ = font_list_.DeriveWithStyle(style);
-  }
+  void SetStyle(int style) { font_list_ = font_list_.DeriveWithStyle(style); }
 
   gfx::Font::Weight GetWeight() const { return font_list_.GetFontWeight(); }
   void SetWeight(gfx::Font::Weight weight) {
-    font_list_ = base_font_.DeriveWithWeight(weight);
+    font_list_ = font_list_.DeriveWithWeight(weight);
   }
 
  private:
   // The font used for drawing the text.
   gfx::FontList font_list_;
 
-  // The font without any bold attributes. Mac font APIs struggle to derive UI
-  // fonts from a base font that isn't NORMAL or BOLD.
-  gfx::FontList base_font_;
-
   // The text to draw.
   base::string16 text_;
 
@@ -144,7 +126,7 @@ Checkbox* TextExample::AddCheckbox(GridLayout* layout, const char* name) {
 
 Combobox* TextExample::AddCombobox(GridLayout* layout,
                                    const char* name,
-                                   const char* const* strings,
+                                   const char** strings,
                                    int count) {
   layout->StartRow(0, 0);
   layout->AddView(new Label(base::ASCIIToUTF16(name)));
@@ -181,13 +163,11 @@ void TextExample::CreateExampleView(View* container) {
                            arraysize(kPrefixOptions));
   text_cb_ = AddCombobox(layout, "Example Text", kTextExamples,
                          arraysize(kTextExamples));
-  weight_cb_ = AddCombobox(layout, "Font Weight", kWeightLabels,
-                           arraysize(kWeightLabels));
-  weight_cb_->SelectValue(base::ASCIIToUTF16("Normal"));
 
   layout->StartRow(0, 0);
   multiline_checkbox_ = AddCheckbox(layout, "Multiline");
   break_checkbox_ = AddCheckbox(layout, "Character Break");
+  bold_checkbox_ = AddCheckbox(layout, "Bold");
   italic_checkbox_ = AddCheckbox(layout, "Italic");
   underline_checkbox_ = AddCheckbox(layout, "Underline");
 
@@ -211,6 +191,8 @@ void TextExample::ButtonPressed(Button* button, const ui::Event& event) {
   SetFlagFromCheckbox(underline_checkbox_, &style, gfx::Font::UNDERLINE);
   text_view_->set_flags(flags);
   text_view_->SetStyle(style);
+  text_view_->SetWeight(bold_checkbox_->checked() ? gfx::Font::Weight::BOLD
+                                                  : gfx::Font::Weight::NORMAL);
   text_view_->SchedulePaint();
 }
 
@@ -272,8 +254,6 @@ void TextExample::OnPerformAction(Combobox* combobox) {
         flags |= gfx::Canvas::HIDE_PREFIX;
         break;
     }
-  } else if (combobox == weight_cb_) {
-    text_view_->SetWeight(kFontWeights[combobox->selected_index()]);
   }
   text_view_->set_flags(flags);
   text_view_->SchedulePaint();

ui/views/examples/text_example.h

@@ -38,7 +38,7 @@ class VIEWS_EXAMPLES_EXPORT TextExample : public ExampleBase,
   // Creates and adds a combobox to the layout.
   Combobox* AddCombobox(GridLayout* layout,
                         const char* name,
-                        const char* const* strings,
+                        const char** strings,
                         int count);
 
   // ButtonListener:
@@ -63,15 +63,15 @@ class VIEWS_EXAMPLES_EXPORT TextExample : public ExampleBase,
   // Combo box to choose one of the sample texts.
   Combobox* text_cb_;
 
-  // Combo box to choose a font weight.
-  Combobox* weight_cb_;
-
   // Check box to enable/disable multiline text drawing.
   Checkbox* multiline_checkbox_;
 
   // Check box to enable/disable character break behavior.
   Checkbox* break_checkbox_;
 
+  // Check box to enable/disable bold style.
+  Checkbox* bold_checkbox_;
+
   // Check box to enable/disable italic style.
   Checkbox* italic_checkbox_;