Keep track of number of queries in the query cache (#776)

* Implement schema versions

* Style fixes

* newlines, copyrights, assumptions

* Fix nullability

* Raw ptr -> shared_ptr

* kVersionTableGlobal -> kVersionGlobalTable

* Drop utils, move into static methods

* Drop extra include

* Add a few more comments

* Move version constant into migrations file

* formatting?

* Fix comment

* Split add and update queryData

* Work on adding targetCount

* More work on count

* Using shared_ptr

* Implement count for query cache

* use quotes

* Add cast

* Styling

* Revert year bump in copyright

* Add adversarial key to migration test

* Add comment

* Fix style

1 files changed, 14 insertions, 0 deletions

diff --git a/Firestore/Source/Local/FSTMemoryQueryCache.mm b/Firestore/Source/Local/FSTMemoryQueryCache.mm
index bcab174..56d5699 100644
--- a/Firestore/Source/Local/FSTMemoryQueryCache.mm
+++ b/Firestore/Source/Local/FSTMemoryQueryCache.mm
@@ -90,6 +90,20 @@ NS_ASSUME_NONNULL_BEGIN
   }
 }
 
+- (void)updateQueryData:(FSTQueryData *)queryData group:(FSTWriteGroup *)group {
+  self.queries[queryData.query] = queryData;
+  if (queryData.targetID > self.highestTargetID) {
+    self.highestTargetID = queryData.targetID;
+  }
+  if (queryData.sequenceNumber > self.highestListenSequenceNumber) {
+    self.highestListenSequenceNumber = queryData.sequenceNumber;
+  }
+}
+
+- (int32_t)count {
+  return (int32_t)[self.queries count];
+}
+
 - (void)removeQueryData:(FSTQueryData *)queryData group:(__unused FSTWriteGroup *)group {
   [self.queries removeObjectForKey:queryData.query];
   [self.references removeReferencesForID:queryData.targetID];