Decrement size of pending write queue by correct amount

The pending write events vector is destructed before using its size to
decrement the number of events on the pending write events queue which
may cause the value decrement by 0 instead of the actual number of
events removed.

Bug: 147686560
Test: Build and load onto device with fake subhals
Change-Id: I7b6c6231eacfa89b0dd55bc405b235d34be5ff46

sensors/2.0/multihal/HalProxy.cpp

@@ -486,15 +486,14 @@ void HalProxy::handlePendingWrites() {
                 }
             }
             lock.lock();
+            mSizePendingWriteEventsQueue -= numToWrite;
             if (pendingWriteEvents.size() > eventQueueSize) {
                 // TODO(b/143302327): Check if this erase operation is too inefficient. It will copy
                 // all the events ahead of it down to fill gap off array at front after the erase.
                 pendingWriteEvents.erase(pendingWriteEvents.begin(),
                                          pendingWriteEvents.begin() + eventQueueSize);
-                mSizePendingWriteEventsQueue -= eventQueueSize;
             } else {
                 mPendingWriteEventsQueue.pop();
-                mSizePendingWriteEventsQueue -= pendingWriteEvents.size();
             }
         }
     }