Delete unused chrome://fallback-icon/ handling

components/favicon_base/fallback_icon_style.h

Index: components/favicon_base/fallback_icon_style.h
diff --git a/components/favicon_base/fallback_icon_style.h b/components/favicon_base/fallback_icon_style.h
index 925773080eb1343bb95a352c89126dea01329a12..0680d54eab6fd25e946c706a40690d1298411d01 100644
--- a/components/favicon_base/fallback_icon_style.h
+++ b/components/favicon_base/fallback_icon_style.h
@@ -17,8 +17,6 @@ struct FallbackIconStyle {
   FallbackIconStyle();
   ~FallbackIconStyle();
 
-  // If any member changes, also update FallbackIconStyleBuilder.
-
   // Icon background fill color.
   SkColor background_color;
   bool is_default_background_color;
@@ -26,21 +24,9 @@ struct FallbackIconStyle {
   // Icon text color.
   SkColor text_color;
 
-  // Ratio in [0.0, 1.0] of the text font size (pixels) to the icon size.
-  double font_size_ratio;
-
-  // The roundness of the icon's corners. 0 => square icon, 1 => circle icon.
-  double roundness;
-
   bool operator==(const FallbackIconStyle& other) const;
 };
 
-// Reassigns |style|'s |text_color| to matches well against |background_color|.
-void MatchFallbackIconTextColorAgainstBackgroundColor(FallbackIconStyle* style);
-
-// Returns whether |style| values are within bounds.
-bool ValidateFallbackIconStyle(const FallbackIconStyle& style);
-
 // Set |style|'s background color to the dominant color of |bitmap_data|,
 // clamping luminance down to a reasonable maximum value so that light text is
 // readable.