Refactor sensor list in SensorService

Refactor sensor lists management logic in sensorservice:
  * Factor all sensor list management code into a separate class.
  * Remove error-prone repeated sensor lists.
  * Solve synchronization issue when sensor is added or removed during runtime.
  * Switch to STL containers.

Bug: b/27911774

Change-Id: I94d5571e1fa3166dbe893ffac2a2a7584be6349c
diff --git a/services/sensorservice/Android.mk b/services/sensorservice/Android.mk
index 57c56a6..85e96d6 100644
--- a/services/sensorservice/Android.mk
+++ b/services/sensorservice/Android.mk
@@ -16,6 +16,7 @@
     SensorEventConnection.cpp \
     MostRecentEventLogger.cpp \
     SensorRecord.cpp \
+    SensorList.cpp \
 
 
 LOCAL_CFLAGS:= -DLOG_TAG=\"SensorService\"