Remove obsolete/infeasible TODOs

(a) Clean up LogEvent::parseBuffer - having those variables be member
variables really helps with code readability.

(b) Don't hold locks when writing to pipe within ShellSubscriber -
ag/150969574 describes why holding a lock is necessary.

Test: m
Bug: 150312423 (allows this bug to be marked as obsolete)
Change-Id: I4903de1dc87a552932b70e5975a7cde91df05b3b

cmds/statsd/src/logd/LogEvent.h

@@ -218,9 +218,6 @@ private:
      * The below three variables are only valid during the execution of
      * parseBuffer. There are no guarantees about the state of these variables
      * before/after.
-     *
-     * TODO (b/150312423): These shouldn't be member variables. We should pass
-     * them around as parameters.
      */
     uint8_t* mBuf;
     uint32_t mRemainingLen; // number of valid bytes left in the buffer being parsed

cmds/statsd/src/shell/ShellSubscriber.cpp

@@ -152,7 +152,6 @@ void ShellSubscriber::startPull(int64_t myToken) {
                 mPullerMgr->Pull(pullInfo.mPullerMatcher.atom_id(), uids, &data);
                 VLOG("pulled %zu atoms with id %d", data.size(), pullInfo.mPullerMatcher.atom_id());
 
-                // TODO(b/150969574): Don't write to a pipe while holding a lock.
                 if (!writePulledAtomsLocked(data, pullInfo.mPullerMatcher)) {
                     mSubscriptionInfo->mClientAlive = false;
                     mSubscriptionShouldEnd.notify_one();