Merge pull request #5 from douglasjunior/patch-3

Make 'com.google.android.gms:play-services-gcm' use optional.

android/src/main/java/com/learnium/RNDeviceInfo/RNDeviceModule.java

@@ -12,8 +12,6 @@ import android.provider.Settings.Secure;
 import android.webkit.WebSettings;
 import android.telephony.TelephonyManager;
 
-import com.google.android.gms.iid.InstanceID;
-
 import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContextBaseJavaModule;
 import com.facebook.react.bridge.ReactMethod;
@@ -114,7 +112,11 @@ public class RNDeviceModule extends ReactContextBaseJavaModule {
       e.printStackTrace();
     }
 
-    constants.put("instanceId", InstanceID.getInstance(this.reactContext).getId());
+    try {
+      if (Class.forName("com.google.android.gms.iid.InstanceID") != null) {
+        constants.put("instanceId", com.google.android.gms.iid.InstanceID.getInstance(this.reactContext).getId());
+      }
+    } catch (ClassNotFoundException e) {}
     constants.put("deviceName", deviceName);
     constants.put("systemName", "Android");
     constants.put("systemVersion", Build.VERSION.RELEASE);