Circumvent icon setting on Android

Apparently the Firefox on Android API doesn't support setIcon, so it
crashes basically the whole core functionality. So if we're on Android,
just skip that part. This fixes #22.

I don't have Android so I can't test this fix. Hopefully it works.

background.js

@@ -39,14 +39,24 @@ function isTresspassing() {
         // If result is not empty, then is tresspassing.
         if (result.length > 0) {
             // If tresspassing, then show so in the extension icon.
-            browser.browserAction.setIcon({
-                    path: { 48: 'icons/monastery_lock.svg'},
+            // This doesn't work on android so adjust accordingly
+            browser.runtime.getPlatformInfo().then(info => {
+                if (info.os == "android") {
+                    browser.browserAction.setIcon({
+                        path: { 48: 'icons/monastery_lock.svg'},
+                    });
+                }
             });
             return true;
         } else {
             // If not tresspassing, make sure icon is back to normal.
-            browser.browserAction.setIcon({
-                    path: { 48: 'icons/monastery.svg'},
+            // This doesn't work on android so adjust accordingly
+            browser.runtime.getPlatformInfo().then(info => {
+                if (info.os == "android") {
+                    browser.browserAction.setIcon({
+                        path: { 48: 'icons/monastery.svg'},
+                    });
+                }
             });
             return false;
         }

manifest.json

@@ -2,7 +2,7 @@
 
     "manifest_version": 2,
     "name": "Monastery",
-    "version": "1.3.1",
+    "version": "1.3.2",
     "applications": {
         "gecko": {
             "id": "[email protected]",