[JS IR] Improve debug info for functions with default parameters

Don't generate unnecessary mappings so that the user doesn't need to
step in many times to get where they want

#KT-46276

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/JsDefaultArgumentStubGenerator.kt

@@ -62,7 +62,7 @@ class JsDefaultArgumentStubGenerator(override val context: JsIrBackendContext) :
     }
 
     private fun IrFunction.introduceDefaultResolution(): IrFunction {
-        val irBuilder = context.createIrBuilder(symbol, startOffset, endOffset)
+        val irBuilder = context.createIrBuilder(symbol, UNDEFINED_OFFSET, UNDEFINED_OFFSET)
 
         val variables = mutableMapOf<IrValueParameter, IrValueParameter>()
 
@@ -140,7 +140,7 @@ class JsDefaultArgumentStubGenerator(override val context: JsIrBackendContext) :
 
     override fun IrFunction.generateDefaultStubBody(originalDeclaration: IrFunction): IrBody {
         val ctx = context
-        val irBuilder = context.createIrBuilder(symbol, startOffset, endOffset)
+        val irBuilder = context.createIrBuilder(symbol, UNDEFINED_OFFSET, UNDEFINED_OFFSET)
 
         val variables = mutableMapOf<IrValueParameter, IrValueDeclaration>().apply {
             originalDeclaration.dispatchReceiverParameter?.let {
@@ -154,7 +154,7 @@ class JsDefaultArgumentStubGenerator(override val context: JsIrBackendContext) :
             }
         }
 
-        return irBuilder.irBlockBody(this) {
+        return irBuilder.irBlockBody(UNDEFINED_OFFSET, UNDEFINED_OFFSET) {
             +valueParameters.zip(originalDeclaration.valueParameters)
                 .mapNotNull { (new, original) ->
                     createResolutionStatement(
@@ -244,4 +244,4 @@ class JsDefaultArgumentStubGenerator(override val context: JsIrBackendContext) :
 
     private fun IrFunction.hasDefaultArgs(): Boolean =
         valueParameters.any { it.defaultValue != null }
-}
+}

compiler/testData/debug/stepping/defaultParameter.kt

@@ -27,9 +27,7 @@ fun box() {
 // test.kt:11 box
 // test.kt:3 <init>
 // test.kt:11 box
+// test.kt:6 foo$default
 // test.kt:4 computeParam
-// test.kt:6 foo$default
-// test.kt:6 foo$default
 // test.kt:7 foo
-// test.kt:6 foo$default
+// test.kt:12 box
-// test.kt:12 box

js/js.translator/testData/lineNumbers/complexExpressionAsDefaultArgument.kt

@@ -11,5 +11,5 @@ fun baz() = 1
 
 fun bar() = 2
 
-// LINES(JS):    1       3 3 2 2 4 3 4 4 4 5 5     2 8 8 10 10 10    12 12 12
+// LINES(JS):    1   3 3 2 2 4 3 4 4 4 5 5 2 8 8 10 10 10    12 12 12
-// LINES(JS_IR): 1 * 1 1 3 3             4 5   1 *   8 8 10 10 10 10 12 12 12 12
+// LINES(JS_IR): 1 * 3 3             4 5   * 8 8 10 10 10 10 12 12 12 12

js/js.translator/testData/lineNumbers/dataClass.kt

@@ -4,6 +4,4 @@ data class A(
 )
 
 // LINES(JS):    1 2 3 * 1 2 2 1 3 3 1 1 1 2 3 1 1 1 2 3 1 1 1 2 3 1 1 1 1 1 2 3
-
+// LINES(JS_IR): 1 1 2 2 3 3 2 2 2 3 3 3 1 1 1 1 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
-// FIXME: componentN function body should point to the corresponding property.
-// LINES(JS_IR): 1 1 2 2 3 3 2 2 2 3 3 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

js/js.translator/testData/lineNumbers/memberFunWithDefaultParam.kt

@@ -11,4 +11,4 @@ class B : A() {
 }
 
 // LINES(JS):    1   2 2 2 2 2 2 2 2 2 4 4 4 * 7 7 8 10 9 9
-// LINES(JS_IR): 1 1 2 2 2 2 2 2 2     4 4 4 7 7 7 8    9 9
+// LINES(JS_IR): 1 1 2 2 2 2 2 *       4 4 4 7 7 7 8    9 9

js/js.translator/testData/lineNumbers/optionalArgs.kt

@@ -7,5 +7,5 @@ fun box(
     println(y)
 }
 
-// LINES(JS):    1 8 2 2 2 2     3 3 3 4   6 6 7 7
+// LINES(JS):    1 8 2 2 2 2     3 3 3 4 6 6 7 7
-// LINES(JS_IR): 1 1 2       1 1       4 1 6 6 7 7
+// LINES(JS_IR): 1   2                 4 6 6 7 7