Include GPS location as a fallback. Only read it passively.

chrome/android/java/src/org/chromium/chrome/browser/omnibox/geo/GeolocationTracker.java

Index: chrome/android/java/src/org/chromium/chrome/browser/omnibox/geo/GeolocationTracker.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/omnibox/geo/GeolocationTracker.java b/chrome/android/java/src/org/chromium/chrome/browser/omnibox/geo/GeolocationTracker.java
index dfac566a7f743e3a4f2a0683c7d519b53f460db1..076fb175b6aec14e391a2c45f888e0f9f8e875f1 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/omnibox/geo/GeolocationTracker.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/omnibox/geo/GeolocationTracker.java
@@ -4,13 +4,17 @@
 
 package org.chromium.chrome.browser.omnibox.geo;
 
+import android.Manifest;
 import android.content.Context;
+import android.content.pm.PackageManager;
 import android.location.Location;
 import android.location.LocationListener;
 import android.location.LocationManager;
 import android.os.Bundle;
 import android.os.Handler;
+import android.os.Process;
 
+import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.annotations.SuppressFBWarnings;
@@ -24,7 +28,8 @@ import org.chromium.base.annotations.SuppressFBWarnings;
 class GeolocationTracker {
 
     private static SelfCancelingListener sListener;
-    private static Location sLocationForTesting;
+    private static Location sNetworkLocationForTesting;
+    private static Location sGpsLocationForTesting;
     private static boolean sUseLocationForTesting;
 
     private static class SelfCancelingListener implements LocationListener {
@@ -78,13 +83,37 @@ class GeolocationTracker {
     }
 
     /**
-     * Returns the last known location from the network provider or null if none is available.
+     * Returns the last known location or null if none is available.
+     *
+     * @param includeGpsFallback Whether the gps provider should also be used as a fallback.
+     *        Otherwise only the network provider will be used.
      */
-    static Location getLastKnownLocation(Context context) {
-        if (sUseLocationForTesting) return sLocationForTesting;
+    static Location getLastKnownLocation(Context context, boolean includeGpsFallback) {
+        if (sUseLocationForTesting) {
+            return chooseLocation(
+                    sNetworkLocationForTesting, sGpsLocationForTesting, includeGpsFallback);
+        }
+
+        if (!hasPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION)) {
+            // Do not call location manager without permissions
+            return null;
+        }
+
         LocationManager locationManager =
                 (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
-        return locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
+        Location networkLocation =
+                locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
+        // If no GPS location has been request, just return the network location. For efficiency,
+        // don't even get the GPS location.
+        if (!includeGpsFallback) {
+            return networkLocation;
+        }
+        Location gpsLocation = null;
+        if (hasPermission(context, Manifest.permission.ACCESS_FINE_LOCATION)) {
+            // Only try to get GPS location when ACCESS_FINE_LOCATION is granted.
+            gpsLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
+        }
+        return chooseLocation(networkLocation, gpsLocation, includeGpsFallback);
     }
 
     /**
@@ -96,6 +125,10 @@ class GeolocationTracker {
     static void refreshLastKnownLocation(Context context, long maxAge) {
         ThreadUtils.assertOnUiThread();
 
+        if (!hasPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION)) {
+            return;
+        }
+
         // We're still waiting for a location update.
         if (sListener != null) return;
 
@@ -112,8 +145,30 @@ class GeolocationTracker {
     }
 
     @VisibleForTesting
-    static void setLocationForTesting(Location location) {
-        sLocationForTesting = location;
+    static void setLocationForTesting(
+            Location networkLocationForTesting, Location gpsLocationForTesting) {
+        sNetworkLocationForTesting = networkLocationForTesting;
+        sGpsLocationForTesting = gpsLocationForTesting;
         sUseLocationForTesting = true;
     }
+
+    private static boolean hasPermission(Context context, String permission) {
+        return ApiCompatibilityUtils.checkPermission(
+                       context, permission, Process.myPid(), Process.myUid())
+                == PackageManager.PERMISSION_GRANTED;
+    }
+
+    private static Location chooseLocation(
+            Location networkLocation, Location gpsLocation, boolean includeGpsFallback) {
+        if (!includeGpsFallback || gpsLocation == null) {
+            return networkLocation;
+        }
+
+        if (networkLocation == null) {
+            return gpsLocation;
+        }
+
+        // Both are not null, take the younger one.
+        return networkLocation.getTime() > gpsLocation.getTime() ? networkLocation : gpsLocation;
+    }
 }