[Sensors] Consider maximum supported frequency

device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensor.java

Index: device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensor.java
diff --git a/device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensor.java b/device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensor.java
index 2da8e583d0aeb2875e2f46366f49737d634104bf..1d825fe3ac83e358ca644aaa61cbefa298fdf031 100644
--- a/device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensor.java
+++ b/device/generic_sensor/android/java/src/org/chromium/device/sensors/PlatformSensor.java
@@ -22,6 +22,7 @@ import java.util.List;
 @JNINamespace("device")
 public class PlatformSensor implements SensorEventListener {
     private static final double MICROSECONDS_IN_SECOND = 1000000;
+    private static final double SECONDS_IN_MICROSECOND = 0.000001d;

[timvolodine, 2016/11/03 17:32:55]

why not use import java.util.concurrent.TimeUnit for conversions instead?

[Mikhail, 2016/11/04 21:17:44]

That API operates with 'long' type and loses precision.
https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/TimeUnit.html

     private static final double SECONDS_IN_NANOSECOND = 0.000000001d;
 
     /**
@@ -124,6 +125,17 @@ public class PlatformSensor implements SensorEventListener {
     }
 
     /**
+     * Returns maximum sampling frequency supported by the sensor.
+     *
+     * @return double frequency in Hz.
+     */
+    @CalledByNative
+    protected double getMaximumSupportedFrequency() {
+        if (mMinDelayUsec == 0) return getDefaultConfiguration();
+        return 1 / (mMinDelayUsec * SECONDS_IN_MICROSECOND);
+    }
+
+    /**
      * Requests sensor to start polling for data.
      *
      * @return boolean true if successful, false otherwise.