Add 'package' argument to IconData (#12560)

packages/flutter/lib/src/cupertino/icons.dart

@@ -27,35 +27,36 @@ import 'package:flutter/widgets.dart';
 class CupertinoIcons {
   CupertinoIcons._();
 
-  static const String iconFont = 'packages/cupertino_icons/CupertinoIcons';
+  static const String iconFont = 'CupertinoIcons';
+  static const String iconFontPackage = 'cupertino_icons';
 
   // Manually maintained list
 
-  static const IconData left_chevron = const IconData(0xf3f0, fontFamily: iconFont);
+  static const IconData left_chevron = const IconData(0xf3f0, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData right_chevron = const IconData(0xf3f2, fontFamily: iconFont);
+  static const IconData right_chevron = const IconData(0xf3f2, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData share = const IconData(0xf4ca, fontFamily: iconFont);
+  static const IconData share = const IconData(0xf4ca, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData book = const IconData(0xf3e7, fontFamily: iconFont);
+  static const IconData book = const IconData(0xf3e7, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData info = const IconData(0xf44c, fontFamily: iconFont);
+  static const IconData info = const IconData(0xf44c, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData reply = const IconData(0xf4c6, fontFamily: iconFont);
+  static const IconData reply = const IconData(0xf4c6, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData conversation_bubble = const IconData(0xf3fb, fontFamily: iconFont);
+  static const IconData conversation_bubble = const IconData(0xf3fb, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData profile_circled = const IconData(0xf419, fontFamily: iconFont);
+  static const IconData profile_circled = const IconData(0xf419, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData plus_circled = const IconData(0xf48a, fontFamily: iconFont);
+  static const IconData plus_circled = const IconData(0xf48a, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData minus_circled = const IconData(0xf463, fontFamily: iconFont);
+  static const IconData minus_circled = const IconData(0xf463, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData flag = const IconData(0xf42c, fontFamily: iconFont);
+  static const IconData flag = const IconData(0xf42c, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData search = const IconData(0xf4c6, fontFamily: iconFont);
+  static const IconData search = const IconData(0xf4c6, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData check_mark = const IconData(0xf41e, fontFamily: iconFont);
+  static const IconData check_mark = const IconData(0xf41e, fontFamily: iconFont, fontPackage: iconFontPackage);
 
-  static const IconData check_mark_circled = const IconData(0xf41f, fontFamily: iconFont);
+  static const IconData check_mark_circled = const IconData(0xf41f, fontFamily: iconFont, fontPackage: iconFontPackage);
 }
\ No newline at end of file

packages/flutter/lib/src/widgets/icon.dart

@@ -132,6 +132,7 @@ class Icon extends StatelessWidget {
                   color: iconColor,
                   fontSize: iconSize,
                   fontFamily: icon.fontFamily,
+                  package: icon.fontPackage,
                 ),
               ),
             ),

packages/flutter/lib/src/widgets/icon_data.dart

@@ -14,9 +14,13 @@ class IconData {
   ///
   /// Rarely used directly. Instead, consider using one of the predefined icons
   /// like the [Icons] collection.
+  ///
+  /// The [fontPackage] argument must be non-null when using a font family that
+  /// is included in a package. This is used when selecting the font.
   const IconData(
     this.codePoint, {
     this.fontFamily,
+    this.fontPackage,
   });
 
   /// The Unicode code point at which this icon is stored in the icon font.
@@ -25,6 +29,9 @@ class IconData {
   /// The font family from which the glyph for the [codePoint] will be selected.
   final String fontFamily;
 
+  // The name of the package from which the font family is included.
+  final String fontPackage;
+
   @override
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)