M81 FIS cherry pick of #6570 (#6616)

* FIS: Additional FIRInstallationsItem validation (#6570)

* FIS API tests for no FID in response

* FIRInstallationsIDControllerTests: test names

* FIRInstallationsIDControllerTests: corrupted storage tests

* FIRInstallationsItem validation

* Fix FIRInstallationsItem.IIDDefaultToken copy

* Improve error description.

* FIRInstallationsItem validation error

* FIRInstallationsItem validation tests

* ./scripts/style.sh

* FIRInstallationsIDController: validate stored installation

* FIRInstallationsAPIService installation validation

* Changelog

* Update versions

* patch version

* release manifest

Author: maksymmalyhin

FirebaseInstallations/Source/Library/InstallationsAPI/FIRInstallationsAPIService.m

@@ -363,6 +363,20 @@ - (NSString *)SDKVersion {
   return result;
 }
 
+#pragma mark - Validation
+
+- (FBLPromise<FIRInstallationsItem *> *)validateInstallation:(FIRInstallationsItem *)installation {
+  FBLPromise<FIRInstallationsItem *> *result = [FBLPromise pendingPromise];
+
+  NSError *validationError;
+  if ([installation isValid:&validationError]) {
+    [result fulfill:installation];
+  } else {
+    [result reject:validationError];
+  }
+  return result;
+}
+
 #pragma mark - JSON
 
 - (void)setJSONHTTPBody:(NSDictionary<NSString *, id> *)body