Use signature inheritance when method types are unchanged

lib/runtime/dart/math.js

 var math = dart.defineLibrary(math, {});
 var core = dart.import(core);
 var _js_helper = dart.lazyImport(_js_helper);
 (function(exports, core, _js_helper) {
   'use strict';
   class _JenkinsSmiHash extends core.Object {
     static combine(hash, value) {
       hash = 536870911 & dart.notNull(hash) + dart.notNull(value);
       hash = 536870911 & dart.notNull(hash) + ((524287 & dart.notNull(hash)) << 10);
       return dart.notNull(hash) ^ dart.notNull(hash) >> 6;
@@ skipping 58 matching lines @@
       }
       squaredDistanceTo(other) {
         dart.as(other, Point$(T));
         let dx = this.x['-'](other.x);
         let dy = this.y['-'](other.y);
         return dart.as(dart.notNull(dx) * dart.notNull(dx) + dart.notNull(dy) * dart.notNull(dy), T);
       }
     }
     dart.setSignature(Point, {
       methods: () => ({
-        toString: dart.functionType(core.String, []),
-        '==': dart.functionType(core.bool, [dart.dynamic]),
         '+': dart.functionType(Point$(T), [Point$(T)]),
         '-': dart.functionType(Point$(T), [Point$(T)]),
         '*': dart.functionType(Point$(T), [core.num]),
         distanceTo: dart.functionType(core.double, [Point$(T)]),
         squaredDistanceTo: dart.functionType(T, [Point$(T)])
       })
     });
     return Point;
   });
   let Point = Point$();
   class Random extends core.Object {
     Random(seed) {
       if (seed === void 0)
         seed = null;
       return seed == null ? dart.const(new _JSRandom()) : new _Random(seed);
     }
   }
-  dart.setSignature(Random, {});
   let _RectangleBase$ = dart.generic(function(T) {
     class _RectangleBase extends core.Object {
       _RectangleBase() {
       }
       get right() {
         return dart.as(this.left['+'](this.width), T);
       }
       get bottom() {
         return dart.as(this.top['+'](this.height), T);
       }
@@ skipping 46 matching lines @@
       }
       get bottomRight() {
         return new (Point$(T))(dart.as(this.left['+'](this.width), T), dart.as(this.top['+'](this.height), T));
       }
       get bottomLeft() {
         return new (Point$(T))(this.left, dart.as(this.top['+'](this.height), T));
       }
     }
     dart.setSignature(_RectangleBase, {
       methods: () => ({
-        toString: dart.functionType(core.String, []),
-        '==': dart.functionType(core.bool, [dart.dynamic]),
         intersection: dart.functionType(Rectangle$(T), [Rectangle$(T)]),
         intersects: dart.functionType(core.bool, [Rectangle$(core.num)]),
         boundingBox: dart.functionType(Rectangle$(T), [Rectangle$(T)]),
         containsRectangle: dart.functionType(core.bool, [Rectangle$(core.num)]),
         containsPoint: dart.functionType(core.bool, [Point$(core.num)])
       })
     });
     return _RectangleBase;
   });
   let _RectangleBase = _RectangleBase$();
   let Rectangle$ = dart.generic(function(T) {
     class Rectangle extends _RectangleBase$(T) {
       Rectangle(left, top, width, height) {
         this.left = left;
         this.top = top;
         this.width = dart.as(width['<'](0) ? dart.notNull(width['unary-']()) * 0 : width, T);
         this.height = dart.as(height['<'](0) ? dart.notNull(height['unary-']()) * 0 : height, T);
         super._RectangleBase();
       }
       fromPoints(a, b) {
         let left = dart.as(min(a.x, b.x), T);
         let width = dart.as(max(a.x, b.x)['-'](left), T);
         let top = dart.as(min(a.y, b.y), T);
         let height = dart.as(max(a.y, b.y)['-'](top), T);
         return new (Rectangle$(T))(left, top, width, height);
       }
     }
     dart.defineNamedConstructor(Rectangle, 'fromPoints');
-    dart.setSignature(Rectangle, {});
     return Rectangle;
   });
   let Rectangle = Rectangle$();
   let _width = Symbol('_width');
   let _height = Symbol('_height');
   let MutableRectangle$ = dart.generic(function(T) {
     class MutableRectangle extends _RectangleBase$(T) {
       MutableRectangle(left, top, width, height) {
         this.left = left;
         this.top = top;
@@ skipping 22 matching lines @@
       }
       set height(height) {
         dart.as(height, T);
         if (height['<'](0))
           height = dart.as(_clampToZero(height), T);
         this[_height] = height;
       }
     }
     MutableRectangle[dart.implements] = () => [Rectangle$(T)];
     dart.defineNamedConstructor(MutableRectangle, 'fromPoints');
-    dart.setSignature(MutableRectangle, {});
     return MutableRectangle;
   });
   let MutableRectangle = MutableRectangle$();
   function _clampToZero(value) {
     dart.assert(dart.notNull(value) < 0);
     return -dart.notNull(value) * 0;
   }
   dart.fn(_clampToZero, core.num, [core.num]);
   let E = 2.718281828459045;
   let LN10 = 2.302585092994046;
@@ skipping 256 matching lines @@
   exports.sin = sin;
   exports.cos = cos;
   exports.tan = tan;
   exports.acos = acos;
   exports.asin = asin;
   exports.atan = atan;
   exports.sqrt = sqrt;
   exports.exp = exp;
   exports.log = log;
 })(math, core, _js_helper);