The problem is that isActive() was changed to wait on the process exiting. When
the process exits, the member variable referring to the process was getting set
to 0 in the function PluginProcess::processFinished, but when the code in
PluginProcess::isActive after the m_currentProcess->waitForFinished(1000) was
executed, that variable was not checked against NULL value.
This bug can be reproduced with any service by disabling connectivity during
upload.
Changed back PluginProcess::isActive to return immediately with true or false,
depending on whether the plugin is running or not.