Load 'equals' parameter from Java code with the name 'other'

This fixes a lot of warnings on mixed Kotlin+Java code about different names
for the same parameter because we always loaded 'equals' parameter with the
name 'p0', whereas in Kotlin we usually name it 'other'

compiler/testData/loadJava/compiledJavaIncludeObjectMethods/ClassWithObjectMethod.txt

@@ -3,7 +3,7 @@ package test
 public final class ClassWithObjectMethod : java.lang.Object {
     public constructor ClassWithObjectMethod()
     protected/*protected and package*/ open override /*1*/ /*fake_override*/ fun clone(): jet.Any
-    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ p0: jet.Any?): jet.Boolean
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: jet.Any?): jet.Boolean
     protected/*protected and package*/ open override /*1*/ /*fake_override*/ fun finalize(): jet.Unit
     public final override /*1*/ /*fake_override*/ fun getClass(): java.lang.Class<out jet.Any?>
     public open override /*1*/ /*fake_override*/ fun hashCode(): jet.Int

compiler/testData/loadJava/compiledJavaIncludeObjectMethods/InterfaceWithObjectMethods.txt

@@ -2,7 +2,7 @@ package test
 
 public trait InterfaceWithObjectMethods : java.lang.Object {
     public abstract override /*1*/ fun clone(): jet.Any?
-    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ p0: jet.Any?): jet.Boolean
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: jet.Any?): jet.Boolean
     public abstract override /*1*/ fun finalize(): jet.Unit
     public final override /*1*/ /*fake_override*/ fun getClass(): java.lang.Class<out jet.Any?>
     public open override /*1*/ /*fake_override*/ fun hashCode(): jet.Int

core/descriptor.loader.java/src/org/jetbrains/jet/lang/resolve/java/lazy/descriptors/LazyJavaMemberScope.kt

@@ -188,12 +188,25 @@ public abstract class LazyJavaMemberScope(
                     else Pair(jetType, null)
                 }
 
+            val name = if (function.getName().asString() == "equals" &&
+                           jValueParameters.size() == 1 &&
+                           KotlinBuiltIns.getInstance().getNullableAnyType() == outType) {
+                // This is a hack to prevent numerous warnings on Kotlin classes that inherit Java classes: if you override "equals" in such
+                // class without this hack, you'll be warned that in the superclass the name is "p0" (regardless of the fact that it's
+                // "other" in Any)
+                // TODO: fix Java parameter name loading logic somehow (don't always load "p0", "p1", etc.)
+                Name.identifier("other")
+            }
+            else {
+                // TODO: parameter names may be drawn from attached sources, which is slow; it's better to make them lazy
+                javaParameter.getName() ?: Name.identifier("p$index")
+            }
+
             ValueParameterDescriptorImpl(
                     function,
                     index,
                     c.resolveAnnotations(javaParameter),
-                    // TODO: parameter names may be drawn from attached sources, which is slow; it's better to make them lazy
-                    javaParameter.getName() ?: Name.identifier("p$index"),
+                    name,
                     outType,
                     false,
                     varargElementType

idea/testData/quickfix/changeSignature/beforeAddParameterNotAvailableForLibrary.kt

@@ -1,5 +1,5 @@
 // "class org.jetbrains.jet.plugin.quickfix.AddFunctionParametersFix" "false"
-// ERROR: Too many arguments for public open fun equals(p0: jet.Any?): jet.Boolean defined in java.lang.Object
+// ERROR: Too many arguments for public open fun equals(other: jet.Any?): jet.Boolean defined in java.lang.Object
 
 fun f(d: java.lang.Object) {
     d.equals("a", <caret>"b")