Implemented intrinsic <coroutineContext> + tests

backend.native/tests/build.gradle

@@ -1309,6 +1309,16 @@ task coroutines_returnsUnit1(type: RunKonanTest) {
     source = "codegen/coroutines/returnsUnit1.kt"
 }
 
+task coroutines_coroutineContext1(type: RunKonanTest) {
+    goldValue = "EmptyCoroutineContext\n"
+    source = "codegen/coroutines/coroutineContext1.kt"
+}
+
+task coroutines_coroutineContext2(type: RunKonanTest) {
+    goldValue = "EmptyCoroutineContext\n"
+    source = "codegen/coroutines/coroutineContext2.kt"
+}
+
 task AbstractMutableCollection(type: RunKonanTest) {
     expectedExitStatus = 0
     source = "runtime/collections/AbstractMutableCollection.kt"

backend.native/tests/codegen/coroutines/coroutineContext1.kt

@@ -0,0 +1,20 @@
+package codegen.coroutines.coroutineContext1
+
+import kotlin.test.*
+
+import kotlin.coroutines.experimental.*
+import kotlin.coroutines.experimental.intrinsics.*
+
+open class EmptyContinuation(override val context: CoroutineContext = EmptyCoroutineContext) : Continuation<Any?> {
+    companion object : EmptyContinuation()
+    override fun resume(value: Any?) {}
+    override fun resumeWithException(exception: Throwable) { throw exception }
+}
+
+fun builder(c: suspend () -> Unit) {
+    c.startCoroutine(EmptyContinuation)
+}
+
+@Test fun runTest() {
+    builder { println(coroutineContext) }
+}

backend.native/tests/codegen/coroutines/coroutineContext2.kt

@@ -0,0 +1,22 @@
+package codegen.coroutines.coroutineContext2
+
+import kotlin.test.*
+
+import kotlin.coroutines.experimental.*
+import kotlin.coroutines.experimental.intrinsics.*
+
+open class EmptyContinuation(override val context: CoroutineContext = EmptyCoroutineContext) : Continuation<Any?> {
+    companion object : EmptyContinuation()
+    override fun resume(value: Any?) {}
+    override fun resumeWithException(exception: Throwable) { throw exception }
+}
+
+fun builder(c: suspend () -> Unit) {
+    c.startCoroutine(EmptyContinuation)
+}
+
+suspend fun foo() = coroutineContext
+
+@Test fun runTest() {
+    builder { println(foo()) }
+}