allow overriding functions with the same name in the parent in webidl binder

tests/webidl/output.txt

@@ -10,6 +10,7 @@ Child1:7
 588
 14
 28
+Child1::parentFunc(90)
 c1 v2
 Parent:16
 Child1:15

tests/webidl/post.js

@@ -5,6 +5,7 @@ var sme = new Module.Parent(42);
 sme.mulVal(2);
 Module.print('*')
 Module.print(sme.getVal());
+sme.parentFunc(90);
 
 Module.print('c1');
 
@@ -16,6 +17,7 @@ Module.print(c1.getValSqr());
 Module.print(c1.getValSqr(3));
 Module.print(c1.getValTimes()); // default argument should be 1
 Module.print(c1.getValTimes(2));
+c1.parentFunc(90);
 
 Module.print('c1 v2');
 

tests/webidl/test.h

@@ -10,6 +10,7 @@ public:
   Parent(Parent *p, Parent *q); // overload constructor
   int getVal() { return value; }; // inline should work just fine here, unlike Way 1 before
   void mulVal(int mul);
+  void parentFunc() {}
 };
 
 class Child1 : public Parent {
@@ -19,6 +20,7 @@ public:
   int getValSqr() { return value*value; }
   int getValSqr(int more) { return value*value*more; }
   int getValTimes(int times=1) { return value*times; }
+  void parentFunc(int x) { printf("Child1::parentFunc(%d)\n", x); }
 };
 
 // Child2 has vtable, parent does not. Checks we cast child->parent properly - (Parent*)child is not a no-op, must offset

tests/webidl/test.idl

@@ -5,12 +5,14 @@ interface Parent {
   void Parent(long val);
   long getVal();
   void mulVal(long mul);
+  void parentFunc();
 };
 
 interface Child1 {
   void Child1(optional long val);
   long getValSqr(optional long more);
   long getValTimes(optional long times=1);
+  void parentFunc(long x); // redefinition, name collides with parent
 };
 
 Child1 implements Parent;

third_party/WebIDL.py

@@ -649,13 +649,15 @@ class IDLInterface(IDLObjectWithScope):
             # Flag the interface as being someone's consequential interface
             iface.setIsConsequentialInterfaceOf(self)
             additionalMembers = iface.originalMembers;
-            for additionalMember in additionalMembers:
+            for additionalMember in additionalMembers[:]:
                 for member in self.members:
                     if additionalMember.identifier.name == member.identifier.name:
-                        raise WebIDLError(
-                            "Multiple definitions of %s on %s coming from 'implements' statements" %
-                            (member.identifier.name, self),
-                            [additionalMember.location, member.location])
+                        # XXX emscripten: allow such name collisions, ignore parent
+                        additionalMembers.remove(additionalMember)
+                        #raise WebIDLError(
+                        #    "Multiple definitions of %s on %s coming from 'implements' statements" %
+                        #    (member.identifier.name, self),
+                        #    [additionalMember.location, member.location])
             self.members.extend(additionalMembers)
             iface.interfacesImplementingSelf.add(self)