Effects: add DSL for declaration of contracts

- Introduce DSL for declaration of contracts. Functions and classes in
this DSL do not bear any computational semantics: in fact, they all do
not exist on runtime. Whole work of extracting semantics from such calls
is done by special parts of compiler

- To make distinguishing those declarations more robust and
convenient, introduce internal annotation @ContractsDSL

- Turn off InlineChecker inside contracts DSL. We do this, because some
functions from DSL should take any possible lambda, so we can't write
any type besides 'Function<R>'. However, InlineChecker will complain if
we will pass inlined lambda in such function -- though, this is false
positive because we know that functions from contracts DSL will never be
executed

- Change testData on HierarchyTestWithLib, where new enum from
kotlin.internal changed expected output

==========
Effect System introduction: 7/18

libraries/stdlib/src/kotlin/internal/Annotations.kt

@@ -102,3 +102,9 @@ internal enum class RequireKotlinVersionKind {
     COMPILER_VERSION,
     API_VERSION,
 }
+
+/**
+ * Specifies that this declaration is a part of special DSL, used for constructing function's contract.
+ */
+@Retention(AnnotationRetention.BINARY)
+internal annotation class ContractsDsl

libraries/stdlib/src/kotlin/internal/contracts/ContractBuilder.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2010-2017 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package kotlin.internal.contracts
+
+import kotlin.internal.ContractsDsl
+import kotlin.internal.InlineOnly
+
+@ContractsDsl
+internal interface ContractBuilder {
+    @ContractsDsl fun returns(): Returns
+    @ContractsDsl fun returns(value: Any?): Returns
+    @ContractsDsl fun returnsNotNull(): ReturnsNotNull
+    @ContractsDsl fun <R> callsInPlace(lambda: Function<R>, kind: InvocationKind = InvocationKind.UNKNOWN): CallsInPlace
+}
+
+@ContractsDsl
+internal enum class InvocationKind {
+    @ContractsDsl AT_MOST_ONCE,
+    @ContractsDsl AT_LEAST_ONCE,
+    @ContractsDsl EXACTLY_ONCE,
+    @ContractsDsl UNKNOWN
+}
+
+@ContractsDsl
+@InlineOnly
+internal inline fun contract(builder: ContractBuilder.() -> Unit) { }

libraries/stdlib/src/kotlin/internal/contracts/Effect.kt

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2010-2017 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package kotlin.internal.contracts
+
+import kotlin.internal.ContractsDsl
+
+@ContractsDsl
+internal interface Effect
+
+@ContractsDsl
+internal interface ConditionalEffect : Effect
+
+@ContractsDsl
+internal interface SimpleEffect {
+    @ContractsDsl
+    infix fun implies(booleanExpression: Boolean): ConditionalEffect
+}
+
+
+@ContractsDsl
+internal interface Returns : SimpleEffect
+
+@ContractsDsl
+internal interface ReturnsNotNull : SimpleEffect
+
+@ContractsDsl
+internal interface CallsInPlace : SimpleEffect