Introduce 'coroutine'/'suspend' modifiers

compiler/testData/loadJava/compiledKotlin/coroutines/Basic.kt

@@ -0,0 +1,9 @@
+package test
+class Controller {
+    suspend fun suspendFun(x: Continuation<String>) {}
+    operator fun handleResult(x: Int, y: Continuation<Nothing>) {}
+}
+
+fun builder(coroutine c: Controller.() -> Continuation<Unit>) {
+
+}

compiler/testData/loadJava/compiledKotlin/coroutines/Basic.txt

@@ -0,0 +1,9 @@
+package test
+
+public fun builder(/*0*/ coroutine c: test.Controller.() -> kotlin.coroutines.Continuation<kotlin.Unit>): kotlin.Unit
+
+public final class Controller {
+    /*primary*/ public constructor Controller()
+    public final operator fun handleResult(/*0*/ x: kotlin.Int, /*1*/ y: kotlin.coroutines.Continuation<kotlin.Nothing>): kotlin.Unit
+    public final suspend fun suspendFun(/*0*/ x: kotlin.coroutines.Continuation<kotlin.String>): kotlin.Unit
+}