sensor: Allow devices to skip the permission request

This is needed by Samsung devices with pre-M sensor
blobs which have support for SENSOR_TYPE_HEART_RATE
or body sensors in general.
These HALs somehow segfault on the flagged code.

Change-Id: I698f4129e71b683f6f063f00da79f32a5f521149

libs/gui/Android.mk

@@ -91,6 +91,10 @@ ifeq ($(TARGET_BOARD_PLATFORM), tegra3)
 	LOCAL_CFLAGS += -DDONT_USE_FENCE_SYNC
 endif
 
+ifeq ($(TARGET_NO_SENSOR_PERMISSION_CHECK),true)
+LOCAL_CPPFLAGS += -DNO_SENSOR_PERMISSION_CHECK
+endif
+
 include $(BUILD_SHARED_LIBRARY)
 
 ifeq (,$(ONE_SHOT_MAKEFILE))

libs/gui/Sensor.cpp

@@ -267,6 +267,7 @@ Sensor::Sensor(struct sensor_t const* hwSensor, int halVersion)
         }
     }
 
+#ifndef NO_SENSOR_PERMISSION_CHECK
     if (mRequiredPermission.length() > 0) {
         // If the sensor is protected by a permission we need to know if it is
         // a runtime one to determine whether we can use the permission cache.
@@ -277,6 +278,7 @@ Sensor::Sensor(struct sensor_t const* hwSensor, int halVersion)
                     String16(mRequiredPermission));
         }
     }
+#endif
 }
 
 Sensor::~Sensor()