Use signature inheritance when method types are unchanged

lib/runtime/dart/_interceptors.js

Index: lib/runtime/dart/_interceptors.js
diff --git a/lib/runtime/dart/_interceptors.js b/lib/runtime/dart/_interceptors.js
index 2d3a82c0125acc8b88b3ca1fb22e687c8af5d725..2f01d1a8eb341c7265b18487416a9bb671d8da6a 100644
--- a/lib/runtime/dart/_interceptors.js
+++ b/lib/runtime/dart/_interceptors.js
@@ -50,11 +50,7 @@ var _js_embedded_names = dart.import(_js_embedded_names);
     }
   }
   dart.setSignature(Interceptor, {
-    methods: () => ({
-      '==': dart.functionType(core.bool, [core.Object]),
-      toString: dart.functionType(core.String, []),
-      noSuchMethod: dart.functionType(dart.dynamic, [core.Invocation])
-    })
+    methods: () => ({'==': dart.functionType(core.bool, [core.Object])})
   });
   let _isInt32 = Symbol('_isInt32');
   let _tdivFast = Symbol('_tdivFast');
@@ -389,7 +385,6 @@ var _js_embedded_names = dart.import(_js_embedded_names);
       toStringAsExponential: dart.functionType(core.String, [], [core.int]),
       toStringAsPrecision: dart.functionType(core.String, [core.int]),
       toRadixString: dart.functionType(core.String, [core.int]),
-      toString: dart.functionType(core.String, []),
       'unary-': dart.functionType(core.num, []),
       '+': dart.functionType(core.num, [core.num]),
       '-': dart.functionType(core.num, [core.num]),
@@ -958,7 +953,6 @@ var _js_embedded_names = dart.import(_js_embedded_names);
       lastIndexOf: dart.functionType(core.int, [core.Pattern], [core.int]),
       contains: dart.functionType(core.bool, [core.Pattern], [core.int]),
       compareTo: dart.functionType(core.int, [core.String]),
-      toString: dart.functionType(core.String, []),
       get: dart.functionType(core.String, [core.int])
     }),
     statics: () => ({
@@ -1122,9 +1116,7 @@ var _js_embedded_names = dart.import(_js_embedded_names);
     }
   }
   JSBool[dart.implements] = () => [core.bool];
-  dart.setSignature(JSBool, {
-    methods: () => ({toString: dart.functionType(core.String, [])})
-  });
+  dart.setSignature(JSBool, {});
   class JSNull extends Interceptor {
     JSNull() {
       super.Interceptor();
@@ -1147,11 +1139,7 @@ var _js_embedded_names = dart.import(_js_embedded_names);
   }
   JSNull[dart.implements] = () => [core.Null];
   dart.setSignature(JSNull, {
-    methods: () => ({
-      '==': dart.functionType(core.bool, [dart.dynamic]),
-      toString: dart.functionType(core.String, []),
-      noSuchMethod: dart.functionType(dart.dynamic, [core.Invocation])
-    })
+    methods: () => ({'==': dart.functionType(core.bool, [dart.dynamic])})
   });
   class JSIndexable extends core.Object {}
   dart.setSignature(JSIndexable, {});
@@ -1186,9 +1174,7 @@ var _js_embedded_names = dart.import(_js_embedded_names);
       return String(this);
     }
   }
-  dart.setSignature(UnknownJavaScriptObject, {
-    methods: () => ({toString: dart.functionType(core.String, [])})
-  });
+  dart.setSignature(UnknownJavaScriptObject, {});
   // Exports:
   exports.JSArray = JSArray;
   exports.JSMutableArray$ = JSMutableArray$;