* naively remove FSTPath import and source/test files.
* port FieldPath, part I
* port FieldPath, part II
* port ResourcePath, part I
* port ResourcePath, part II
* the grand commit to fix build errors
* use testutil:: helper instead of those from FSTHelpers
* fix test and lint
* use c_str in errmsg directly
* fix
* fix
* make code clean
* fix integration test I missed
* fix to avoid naming collision in preprocessor
* address changes
* address changes
* address changes
* fix: fieldMask are actually shared with different context.
* address changes
* address changes
* 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
* Move all Firestore files to Objective-C++
* Update project file references
* Don't use module imports from Objective-C++
* Use extern "C" for C-accessible globals
* Work around more stringent type checking in Objective-C++
* NSMutableDictionary ivars aren't implicitly casted to NSDictionary
* FSTMaybeDocument callback can't be passed a function that accepts
FSTDocument
* NSComparisonResult can't be multiplied by -1 without casting
* Add a #include <inttypes.h> where needed
* Avoid using C++ keywords as variables
* Remove #if __cplusplus guards