fix all instances of "the the"

pkg/compiler/lib/src/resolution/class_hierarchy.dart

Index: pkg/compiler/lib/src/resolution/class_hierarchy.dart
diff --git a/pkg/compiler/lib/src/resolution/class_hierarchy.dart b/pkg/compiler/lib/src/resolution/class_hierarchy.dart
index 7465a1689a6013f43ac676eefb59a4860f14a1dc..1150c96feb90a46fabbbf43ec0e25b65444d681d 100644
--- a/pkg/compiler/lib/src/resolution/class_hierarchy.dart
+++ b/pkg/compiler/lib/src/resolution/class_hierarchy.dart
@@ -248,7 +248,7 @@ class ClassResolverVisitor extends TypeDefinitionVisitor {
     return enumType;
   }
 
-  /// Resolves the mixed type for [mixinNode] and checks that the the mixin type
+  /// Resolves the mixed type for [mixinNode] and checks that the mixin type
   /// is a valid, non-blacklisted interface type. The mixin type is returned.
   DartType checkMixinType(TypeAnnotation mixinNode) {
     DartType mixinType = resolveType(mixinNode);