KT-2752: remove diagnostic that reports about overridden method having several names from different sources. Generate proxies instead. Fix reporting name clash when two distinct fake overrides require same name.

compiler/testData/codegen/box/bridges/jsName.kt

@@ -0,0 +1,59 @@
+// TARGET_BACKEND: JS
+package foo
+
+interface A {
+    @JsName("foo") fun foo(value: Int): String
+}
+
+interface B {
+    @JsName("bar") fun foo(value: Int): String
+}
+
+open class C : A, B {
+    override fun foo(value: Int) = "C.foo($value)"
+}
+
+class CDerived : C() {
+    override fun foo(value: Int) = "CDerived.foo($value)"
+}
+
+open class D {
+    open fun foo(value: Int) = "D.foo($value)"
+}
+
+class E : D(), A, B
+
+fun box(): String {
+    val a: A = C()
+    assertEquals("C.foo(55)", a.foo(55))
+
+    val b: B = C()
+    assertEquals("C.foo(23)", b.foo(23))
+
+    val a2: A = CDerived()
+    assertEquals("CDerived.foo(55)", a2.foo(55))
+
+    val b2: B = CDerived()
+    assertEquals("CDerived.foo(23)", b2.foo(23))
+
+    val d: dynamic = C()
+    assertEquals("C.foo(42)", d.foo(42))
+    assertEquals("C.foo(99)", d.bar(99))
+
+    val d2: dynamic = CDerived()
+    assertEquals("CDerived.foo(42)", d2.foo(42))
+    assertEquals("CDerived.foo(99)", d2.bar(99))
+
+    val da: A = E()
+    assertEquals("D.foo(55)", da.foo(55))
+
+    val db: B = E()
+    assertEquals("D.foo(23)", db.foo(23))
+
+    val dd: dynamic = E()
+    assertEquals("D.foo(42)", dd.foo(42))
+    assertEquals("D.foo(99)", dd.bar(99))
+    assertEquals("D.foo(88)", dd.`foo_za3lpa$`(88))
+
+    return "OK"
+}

compiler/testData/codegen/box/bridges/jsNative.kt

@@ -13,6 +13,12 @@ class C : A, B {
     override fun foo(value: Int) = "C.foo($value)"
 }
 
+open class D {
+    open fun foo(value: Int) = "D.foo($value)"
+}
+
+class E : D(), A, B
+
 fun box(): String {
     val a: A = C()
     assertEquals("C.foo(55)", a.foo(55))
@@ -24,5 +30,15 @@ fun box(): String {
     assertEquals("C.foo(42)", d.foo(42))
     assertEquals("C.foo(99)", d.`foo_za3lpa$`(99))
 
+    val da: A = E()
+    assertEquals("D.foo(55)", da.foo(55))
+
+    val db: B = E()
+    assertEquals("D.foo(23)", db.foo(23))
+
+    val dd: dynamic = E()
+    assertEquals("D.foo(42)", dd.foo(42))
+    assertEquals("D.foo(99)", dd.`foo_za3lpa$`(99))
+
     return "OK"
 }