TextControl NG: Make ScrollbarThickness() and HasValidAvgCharWidth() static and public

This CL makes ScrollbarThickness() and HasValidAvgCharWidth() of
LayoutTextControl static and public in order to share them with
LayoutNG.

- ScrollbarThickness(): It takes a LayoutBox argument

- HasValidAvgCharWidth(): Pass only Font to it because both of
  SimpleFontData and the family name can be obtained through the Font.

This CL has no behavior changes.

Bug: 1040826
Change-Id: Ie7000ef7cca04284b2b1a6ff934809560d37a2da
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2449094
Commit-Queue: Kent Tamura <tkent@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Auto-Submit: Kent Tamura <tkent@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813654}

third_party/blink/renderer/core/layout/layout_text_control.cc

@@ -81,11 +81,11 @@ void LayoutTextControl::StyleDidChange(StyleDifference diff,
   }
 }
 
-int LayoutTextControl::ScrollbarThickness() const {
-  NOT_DESTROYED();
-  return GetDocument().GetPage()->GetScrollbarTheme().ScrollbarThickness(
-      GetDocument().GetPage()->GetChromeClient().WindowToViewportScalar(
-          GetFrame(), 1.0f));
+// static
+int LayoutTextControl::ScrollbarThickness(const LayoutBox& box) {
+  const Page& page = *box.GetDocument().GetPage();
+  return page.GetScrollbarTheme().ScrollbarThickness(
+      page.GetChromeClient().WindowToViewportScalar(box.GetFrame(), 1.0f));
 }
 
 void LayoutTextControl::ComputeLogicalHeight(
@@ -109,7 +109,7 @@ void LayoutTextControl::ComputeLogicalHeight(
         (StyleRef().OverflowInlineDirection() == EOverflow::kAuto &&
          inner_editor->GetLayoutObject()->StyleRef().OverflowWrap() ==
              EOverflowWrap::kNormal))
-      logical_height += ScrollbarThickness();
+      logical_height += ScrollbarThickness(*this);
 
     // FIXME: The logical height of the inner text box should have been added
     // before calling computeLogicalHeight to avoid this hack.
@@ -179,13 +179,14 @@ static const char* const kFontFamiliesWithInvalidCharWidth[] = {
 // avgCharWidth from the width of a '0'. This only seems to apply to a fixed
 // number of Mac fonts, but, in order to get similar rendering across platforms,
 // we do this check for all platforms.
-bool LayoutTextControl::HasValidAvgCharWidth(const SimpleFontData* font_data,
-                                             const AtomicString& family) {
-  // Some fonts match avgCharWidth to CJK full-width characters.
-  // Heuristic check to avoid such fonts.
+bool LayoutTextControl::HasValidAvgCharWidth(const Font& font) {
+  const AtomicString family = font.GetFontDescription().Family().Family();
+  const SimpleFontData* font_data = font.PrimaryFont();
   DCHECK(font_data);
   if (!font_data)
     return false;
+  // Some fonts match avgCharWidth to CJK full-width characters.
+  // Heuristic check to avoid such fonts.
   const FontMetrics& metrics = font_data->GetFontMetrics();
   if (metrics.HasZeroWidth() &&
       font_data->AvgCharWidth() > metrics.ZeroWidth() * 1.7)
@@ -211,9 +212,8 @@ bool LayoutTextControl::HasValidAvgCharWidth(const SimpleFontData* font_data,
 // static
 float LayoutTextControl::GetAvgCharWidth(const ComputedStyle& style) {
   const Font& font = style.GetFont();
-  const AtomicString family = font.GetFontDescription().Family().Family();
   const SimpleFontData* primary_font = font.PrimaryFont();
-  if (primary_font && HasValidAvgCharWidth(primary_font, family))
+  if (primary_font && HasValidAvgCharWidth(font))
     return roundf(primary_font->AvgCharWidth());
 
   const UChar kCh = '0';

third_party/blink/renderer/core/layout/layout_text_control.h

@@ -49,7 +49,9 @@ class CORE_EXPORT LayoutTextControl : public LayoutBlockFlow {
     return true;
   }
 
+  static int ScrollbarThickness(const LayoutBox& box);
   static float GetAvgCharWidth(const ComputedStyle& style);
+  static bool HasValidAvgCharWidth(const Font& font);
 
  protected:
   LayoutTextControl(TextControlElement*);
@@ -58,16 +60,12 @@ class CORE_EXPORT LayoutTextControl : public LayoutBlockFlow {
   // innerEditorElement may outlive the layout tree.
   TextControlInnerEditorElement* InnerEditorElement() const;
 
-  int ScrollbarThickness() const;
-
   void StyleDidChange(StyleDifference, const ComputedStyle* old_style) override;
 
   void HitInnerEditorElement(HitTestResult&,
                              const HitTestLocation&,
                              const PhysicalOffset& accumulated_offset);
 
-  static bool HasValidAvgCharWidth(const SimpleFontData*,
-                                   const AtomicString& family);
   virtual LayoutUnit PreferredContentLogicalWidth(float char_width) const = 0;
   virtual LayoutUnit ComputeControlLogicalHeight(
       LayoutUnit line_height,

third_party/blink/renderer/core/layout/layout_text_control_multi_line.cc

@@ -61,7 +61,7 @@ LayoutUnit LayoutTextControlMultiLine::PreferredContentLogicalWidth(
   NOT_DESTROYED();
   int factor = To<HTMLTextAreaElement>(GetNode())->cols();
   return static_cast<LayoutUnit>(ceilf(char_width * factor)) +
-         ScrollbarThickness();
+         ScrollbarThickness(*this);
 }
 
 LayoutUnit LayoutTextControlMultiLine::ComputeControlLogicalHeight(

third_party/blink/renderer/core/layout/layout_text_control_single_line.cc

@@ -189,8 +189,7 @@ LayoutUnit LayoutTextControlSingleLine::PreferredContentLogicalWidth(
 
   float max_char_width = 0.f;
   const Font& font = StyleRef().GetFont();
-  AtomicString family = font.GetFontDescription().Family().Family();
-  if (HasValidAvgCharWidth(font.PrimaryFont(), family))
+  if (HasValidAvgCharWidth(font))
     max_char_width = roundf(font.PrimaryFont()->MaxCharWidth());
 
   // For text inputs, IE adds some extra width.