Bug 1524271 - [mozharness] improve mozharness android.py install_apk installation failure message, r=gbrown.

testing/mozharness/mozharness/mozilla/testing/android.py

@@ -323,8 +323,11 @@ class AndroidMixin(object):
         try:
             self.device.install_app(apk)
         except (mozdevice.ADBError, mozdevice.ADBTimeoutError):
-            self.fatal('INFRA-ERROR: Failed to install %s on %s' %
-                       (self.installer_path, self.device_name),
+            self.info('Failed to install %s on %s' %
+                      (self.installer_path, self.device_name),
+                      exc_info=1)
+            self.fatal('INFRA-ERROR: Failed to install %s' %
+                       self.installer_path,
                        EXIT_STATUS_DICT[TBPL_RETRY])
 
     def is_boot_completed(self):