write annotations when dumping structured parcelable

1. Compare annotations after sorting when checkapi
2. Add some testcases
3. Write annotations in the parcelable when aidl --dumpapi

Bug: 120454218
Test: ./runtests.sh
Change-Id: I02e3f3ae3e8ee626f4823128b22d0d4eba6167af
diff --git a/aidl_language.cpp b/aidl_language.cpp
index 0cc11ac..578a3e0 100644
--- a/aidl_language.cpp
+++ b/aidl_language.cpp
@@ -245,7 +245,7 @@
 }
 
 string AidlVariableDeclaration::ToString() const {
-  string ret = type_->ToString() + " " + name_;
+  string ret = type_->Signature() + " " + name_;
   if (default_value_ != nullptr) {
     ret += " = " + ValueString(AidlConstantValueDecorator);
   }