[K/JS, K/Wasm] Optimize simple objects declaration and usage ^Fixed KT-58797

compiler/testData/codegen/box/size/objectsOptimization.kt

@@ -0,0 +1,67 @@
+// TARGET_BACKEND: WASM
+
+// WASM_DCE_EXPECTED_OUTPUT_SIZE: wasm 18_008
+// WASM_DCE_EXPECTED_OUTPUT_SIZE:  mjs 5_451
+
+object Simple
+
+object SimpleWithConstVal {
+   const val MAX = 4
+}
+
+object SimpleWithPureProperty {
+    val text = "Hello"
+}
+
+object SimpleWithPropertyInitializedDurintInit {
+    val text: String
+    init {
+        text = "Hello"
+    }
+}
+
+object SimpleWithFunctionsOnly {
+    fun foo() = "Foo"
+    fun bar() = "Bar"
+}
+
+object SimpleWithDifferentMembers {
+    val foo = "Foo"
+    fun bar() = "Bar"
+}
+
+interface Callable {
+    fun call(): String
+}
+
+object SimpleWithInterface : Callable {
+    override fun call() = "OK"
+}
+
+object UsedGetFieldInside {
+    val anotherText = SimpleWithPureProperty.text
+}
+
+class ClassWithCompanion {
+   companion object
+}
+
+class ClassWithCompanionWithConst {
+    companion object {
+        const val MAX = 5
+    }
+}
+
+fun box(): String {
+    if (Simple !is Any) return "Fail simple object"
+    if (SimpleWithConstVal.MAX != 4) return "Fail simple case with const val"
+    if (SimpleWithPureProperty.text != "Hello") return "Fail simple case with pure property"
+    if (SimpleWithPropertyInitializedDurintInit.text != "Hello") return "Fail simple case with pure property initialized inside init block"
+    if (SimpleWithFunctionsOnly.foo() != "Foo" || SimpleWithFunctionsOnly.bar() != "Bar") return "Fail simple case with functions only"
+    if (SimpleWithInterface.call() != "OK") return "Fail simple case with interface implementing"
+    if (UsedGetFieldInside.anotherText != "Hello") return "Fail object which used another object inside its initialization block"
+    if (ClassWithCompanion.Companion !is Any) return "Fail simple companion object"
+    if (ClassWithCompanionWithConst.MAX != 5) return "Fail simple companion object with const val"
+    SimpleWithDifferentMembers
+    return "OK"
+}