[WASM] Caching string literals in global pool

libraries/stdlib/wasm/src/kotlin/text/StringBuilderWasm.kt

@@ -15,7 +15,7 @@ internal fun insertString(array: CharArray, destinationIndex: Int, value: String
 internal fun unsafeStringFromCharArray(array: CharArray, start: Int, size: Int): String {
     val copy = WasmCharArray(size)
     copyWasmArray(array.storage, copy, start, 0, size)
-    return String(copy)
+    return copy.createString()
 }
 
 internal fun insertInt(array: CharArray, start: Int, value: Int): Int {

libraries/stdlib/wasm/src/kotlin/text/StringsWasm.kt

@@ -75,7 +75,7 @@ public actual fun String(chars: CharArray, offset: Int, length: Int): String {
 
     val copy = WasmCharArray(length)
     copyWasmArray(chars.storage, copy, offset, 0, length)
-    return String(copy)
+    return copy.createString()
 }
 
 /**
@@ -88,7 +88,7 @@ public actual fun CharArray.concatToString(): String {
     val thisLength = thisStorage.len()
     val copy = WasmCharArray(thisLength)
     copyWasmArray(this.storage, copy, 0, 0, thisLength)
-    return String(copy)
+    return copy.createString()
 }
 
 /**
@@ -109,7 +109,7 @@ public actual fun CharArray.concatToString(startIndex: Int = 0, endIndex: Int =
     val length = endIndex - startIndex
     val copy = WasmCharArray(length)
     copyWasmArray(this.storage, copy, startIndex, 0, length)
-    return String(copy)
+    return copy.createString()
 }
 
 /**