Remove StringTable.serializeTo, add JvmProtoBufUtil.writeData

StringTable.serializeTo was effectively only used for JvmStringTable,
but was declared in StringTable because of the usage in
DescriptorSerializer.serialize (which, in turn, was only used from JVM
codegen)

core/metadata.jvm/src/org/jetbrains/kotlin/metadata/jvm/deserialization/JvmProtoBufUtil.kt

@@ -8,8 +8,11 @@ package org.jetbrains.kotlin.metadata.jvm.deserialization
 import org.jetbrains.kotlin.metadata.ProtoBuf
 import org.jetbrains.kotlin.metadata.deserialization.*
 import org.jetbrains.kotlin.metadata.jvm.JvmProtoBuf
+import org.jetbrains.kotlin.metadata.jvm.serialization.JvmStringTable
 import org.jetbrains.kotlin.protobuf.ExtensionRegistryLite
+import org.jetbrains.kotlin.protobuf.MessageLite
 import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
 import java.io.InputStream
 
 object JvmProtoBufUtil {
@@ -46,6 +49,16 @@ object JvmProtoBufUtil {
     private fun InputStream.readNameResolver(strings: Array<String>): JvmNameResolver =
         JvmNameResolver(JvmProtoBuf.StringTableTypes.parseDelimitedFrom(this, EXTENSION_REGISTRY), strings)
 
+    /**
+     * Serializes [message] and [stringTable] into a string array which must be further written to [Metadata.d1]
+     */
+    @JvmStatic
+    fun writeData(message: MessageLite, stringTable: JvmStringTable): Array<String> =
+        BitEncoding.encodeBytes(ByteArrayOutputStream().apply {
+            stringTable.serializeTo(this)
+            message.writeTo(this)
+        }.toByteArray())
+
     // returns JVM signature in the format: "equals(Ljava/lang/Object;)Z"
     fun getJvmMethodSignature(
             proto: ProtoBuf.Function,

core/metadata.jvm/src/org/jetbrains/kotlin/metadata/jvm/serialization/JvmStringTable.kt

@@ -94,7 +94,7 @@ open class JvmStringTable(nameResolver: JvmNameResolver? = null) : StringTable {
         return index
     }
 
-    override fun serializeTo(output: OutputStream) {
+    fun serializeTo(output: OutputStream) {
         with(JvmProtoBuf.StringTableTypes.newBuilder()) {
             addAllRecord(records.map { it.build() })
             addAllLocalName(localNames)