Refactoring. Move specificity relations into TypeSpecificityComparator component.

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/JsPlatformConfigurator.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 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.
@@ -43,5 +43,6 @@ object JsPlatformConfigurator : PlatformConfigurator(
 
         container.useImpl<JsCallChecker>()
         container.useInstance(SyntheticScopes.Empty)
+        container.useInstance(JsTypeSpecificityComparator)
     }
 }

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/JsTypeSpecificityComparator.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2010-2016 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 org.jetbrains.kotlin.js.resolve
+
+import org.jetbrains.kotlin.resolve.calls.results.TypeSpecificityComparator
+import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.isDynamic
+import org.jetbrains.kotlin.types.isFlexible
+
+object JsTypeSpecificityComparator: TypeSpecificityComparator {
+
+    private fun checkOnlyDynamicFlexibleType(type: KotlinType) {
+        if (type.isFlexible()) {
+            assert(type.isDynamic()) {
+                "Unexpected flexible type in Js: $type"
+            }
+        }
+    }
+
+    override fun isDefinitelyLessSpecific(specific: KotlinType, general: KotlinType): Boolean {
+        checkOnlyDynamicFlexibleType(specific)
+        checkOnlyDynamicFlexibleType(general)
+
+        return specific.isDynamic() && !general.isDynamic()
+    }
+}