Parcelize: Enable ParcelableDeclarationChecker with the parcelize plugin

Previously, the ParcelableDeclarationChecker was only enabled as part of
the view extensions. In particular, the checker was not enabled for the
parcelize test suite.

plugins/android-extensions/android-extensions-compiler/testData/parcel/codegen/serializeValue.kt

@@ -1,6 +1,3 @@
-// This test checks that we create calls to readValue/writeValue if there is no other
-// way of serializing properties. In this case, this would fail at runtime.
-
 // CURIOUS_ABOUT writeToParcel, createFromParcel, <clinit>, describeContents
 // WITH_RUNTIME
 
@@ -10,4 +7,4 @@ import android.os.Parcelable
 class Value(val x: Int)
 
 @Parcelize
-class Test(val value: Value) : Parcelable
+class Test(val value: @RawValue Value) : Parcelable