Expose device RSSI and Tx power via the chrome.bluetooth API.

chrome/common/extensions/api/bluetooth.idl

Index: chrome/common/extensions/api/bluetooth.idl
diff --git a/chrome/common/extensions/api/bluetooth.idl b/chrome/common/extensions/api/bluetooth.idl
index b42fce4a6ee865e24072fc621fd1bb87555995e6..cebbf804cbb4af7363dff4c415d806c9e06d9de0 100644
--- a/chrome/common/extensions/api/bluetooth.idl
+++ b/chrome/common/extensions/api/bluetooth.idl
@@ -61,6 +61,23 @@ namespace bluetooth {
     // Indicates whether the device is currently connected to the system.
     boolean? connected;
 
+    // Indicates the RSSI ("received signal strength indication") of the
+    // connection to the device, measured in dBm, to a resolution of 1dBm.
+    // If the device is currently connected, then measures the RSSI of the
+    // connection signal. Otherwise, measures the RSSI of the last inquiry sent
+    // to the device, where available. Absent if unavailable.
+    long? rssi;
+
+    // Indicates the host's current transmit power ("Tx power") for the
+    // connection to the device, measured in dBm, to a resolution of 1dBm.
+    // This value is only available if the device is currently connected.
+    long? currentHostTransmitPower;
+
+    // Indicates the host's maximum transmit power ("Tx power") for the
+    // connection to the device, measured in dBm, to a resolution of 1dBm.
+    // This value is only available if the device is currently connected.
+    long? maximumHostTransmitPower;
+
     // UUIDs of protocols, profiles and services advertised by the device.
     // For classic Bluetooth devices, this list is obtained from EIR data and
     // SDP tables. For Low Energy devices, this list is obtained from AD and