Handle methods descriptor clash in data class

1. Extension functions declared in data classes are generated earlier by `generateMembersDeclaredInClassBody`
2. Extension functions fake override from parent class are generated earlier by `generateFakeOverrideMemberDeclarations`

So it is safe to filter out extension functions inside `generateAdditionalMembersForDataClass`

 #KT-49715
 #KT-51798

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/JsCodegenBoxTestGenerated.java

@@ -9725,6 +9725,12 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/dataClasses/genericParam.kt");
         }
 
+        @Test
+        @TestMetadata("kt49715.kt")
+        public void testKt49715() throws Exception {
+            runTest("compiler/testData/codegen/box/dataClasses/kt49715.kt");
+        }
+
         @Test
         @TestMetadata("mixedParams.kt")
         public void testMixedParams() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrJsCodegenBoxTestGenerated.java

@@ -9767,6 +9767,12 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/dataClasses/genericParam.kt");
         }
 
+        @Test
+        @TestMetadata("kt49715.kt")
+        public void testKt49715() throws Exception {
+            runTest("compiler/testData/codegen/box/dataClasses/kt49715.kt");
+        }
+
         @Test
         @TestMetadata("mixedParams.kt")
         public void testMixedParams() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/testOld/wasm/semantics/IrCodegenBoxWasmTestGenerated.java

@@ -8549,6 +8549,11 @@ public class IrCodegenBoxWasmTestGenerated extends AbstractIrCodegenBoxWasmTest
             runTest("compiler/testData/codegen/box/dataClasses/genericParam.kt");
         }
 
+        @TestMetadata("kt49715.kt")
+        public void testKt49715() throws Exception {
+            runTest("compiler/testData/codegen/box/dataClasses/kt49715.kt");
+        }
+
         @TestMetadata("mixedParams.kt")
         public void testMixedParams() throws Exception {
             runTest("compiler/testData/codegen/box/dataClasses/mixedParams.kt");