Add a section to Site Settings listing USB devices.

chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbInfo.java

Index: chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbInfo.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbInfo.java b/chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbInfo.java
index c48aa1e67453b2924b4b259831a54ea7e39d0edf..5f9e5a24d12e7c5edea9514fed0182e34e1703a5 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbInfo.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbInfo.java
@@ -8,6 +8,9 @@ import java.io.Serializable;
 
 /**
  * USB device information for a given origin.
+ *
+ * When these objects are compared only the identity of the device, not which site has permission to

[Theresa, 2016/08/04 16:39:55]

nit: This sentence feels incomplete. Maybe something like  "... only the
identify of the device is used.." 

[Reilly Grant (use Gerrit), 2016/08/04 19:57:11]

Added a verb.

+ * access it.
  */
 public class UsbInfo implements Serializable {
     private final String mOrigin;
@@ -49,4 +52,18 @@ public class UsbInfo implements Serializable {
     public void revoke() {
         WebsitePreferenceBridge.nativeRevokeUsbPermission(mOrigin, mEmbedder, mObject);
     }
+
+    @Override
+    public int hashCode() {
+        return mObject.hashCode();
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof UsbInfo) {
+            UsbInfo other = (UsbInfo) obj;
+            return mObject.equals(other.mObject);
+        }
+        return false;
+    }
 }