Add MutableMap.remove(K, V) as built-in declaration

Use PlatformDependent annotation to guarantee it's only be available for JDK8
Also adjust type-safe bridges and mutable collection stubs generation

compiler/testData/codegen/java8/writeSignature/mutableMapRemove.kt

@@ -0,0 +1,25 @@
+class KotlinMap1<K, V> : java.util.AbstractMap<K, V>() {
+    override val entries: MutableSet<MutableMap.MutableEntry<K, V>>
+        get() = throw UnsupportedOperationException()
+
+    override fun remove(x: K, y: V) = true
+}
+
+// method: KotlinMap1::remove
+// jvm signature: (Ljava/lang/Object;Ljava/lang/Object;)Z
+// generic signature: null
+
+class KotlinMap2 : java.util.AbstractMap<String, Int>() {
+    override val entries: MutableSet<MutableMap.MutableEntry<String, Int>>
+        get() = throw UnsupportedOperationException()
+
+    override fun remove(x: String, y: Int) = true
+}
+
+// method: KotlinMap2::remove
+// jvm signature: (Ljava/lang/Object;Ljava/lang/Object;)Z
+// generic signature: null
+
+// method: KotlinMap2::remove
+// jvm signature: (Ljava/lang/String;Ljava/lang/Integer;)Z
+// generic signature: null