Force-resolve body in contract computation under lock

Even though acquire/release pattern guarantees memory visibility across
threads, it doesn't prevents concurrent access to critical section (i.e.
to force-resolve of the corresponding body).

This can lead to multiple resolution passes over one and the same PSI in
IDE, which, in turn, leads to 'rewrite at slice'-exceptions. See
KT-30030 for case description and details.

^KT-30030 Fixed

compiler/tests-common/tests/org/jetbrains/kotlin/test/util/RecursiveDescriptorComparator.java

@@ -201,7 +201,7 @@ public class RecursiveDescriptorComparator {
     }
 
     private static void printEffectsIfAny(FunctionDescriptor functionDescriptor, Printer printer) {
-        LazyContractProvider contractProvider = functionDescriptor.getUserData(ContractProviderKey.INSTANCE);
+        AbstractContractProvider contractProvider = functionDescriptor.getUserData(ContractProviderKey.INSTANCE);
         if (contractProvider == null) return;
 
         ContractDescription contractDescription = contractProvider.getContractDescription();