[IR BE] Delegate coroutine naming strategy to platform part

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt

@@ -33,7 +33,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
 
     protected abstract val stateMachineMethodName: Name
     protected abstract fun getCoroutineBaseClass(function: IrFunction): IrClassSymbol
-
+    protected abstract fun nameForCoroutineClass(function: IrFunction): Name
 
     protected abstract fun buildStateMachine(
         originalBody: IrBody, stateMachineFunction: IrFunction,
@@ -258,8 +258,6 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
         val stateMachineFunction: IrFunction
     )
 
-    private var coroutineId = 0
-
     private inner class CoroutineBuilder(val irFunction: IrFunction, val functionReference: IrFunctionReference?) {
 
         private val startOffset = irFunction.startOffset
@@ -273,7 +271,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
                 startOffset, endOffset,
                 DECLARATION_ORIGIN_COROUTINE_IMPL,
                 IrClassSymbolImpl(d),
-                "${irFunction.name}COROUTINE\$${coroutineId++}".synthesizedName,
+                nameForCoroutineClass(irFunction),
                 ClassKind.CLASS,
                 irFunction.visibility,
                 Modality.FINAL,

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

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.ir.backend.js.lower.coroutines
 
+import org.jetbrains.kotlin.backend.common.descriptors.synthesizedName
 import org.jetbrains.kotlin.backend.common.ir.isSuspend
 import org.jetbrains.kotlin.backend.common.lower.AbstractSuspendFunctionsLowering
 import org.jetbrains.kotlin.ir.IrElement
@@ -34,10 +35,13 @@ class JsSuspendFunctionsLowering(ctx: JsIrBackendContext) : AbstractSuspendFunct
     private val coroutineImplResultSymbolSetter = ctx.coroutineImplResultSymbolSetter
 
     private var exceptionTrapId = -1
+    private var coroutineId = 0
 
     override val stateMachineMethodName = Name.identifier("doResume")
     override fun getCoroutineBaseClass(function: IrFunction) = context.ir.symbols.coroutineImpl
 
+    override fun nameForCoroutineClass(function: IrFunction) = "${function.name}COROUTINE\$${coroutineId++}".synthesizedName
+
     override fun buildStateMachine(
         originalBody: IrBody,
         stateMachineFunction: IrFunction,