nsIPluginInstance Interface

 Called to instruct the plugin instance to destroy itself. This
 is called when it become no longer possible to return to the
 plugin instance, either because the browser window's history
 list of pages is being trimmed, or because the window
 containing this page in the history is being closed.

 @result - NS_OK if this operation was successful

void destroy()

 Returns the value of a variable associated with the plugin instance.

 @param aVariable - the plugin instance variable to get
 @param aValue    - the address of where to store the resulting value
 @result          - NS_OK if this operation was successful

void getValue(in nsPluginInstanceVariable aVariable, in voidPtr aValue)

 Handles an event. An nsIEventHandler can also get registered with with
 nsIPluginManager2::RegisterWindow and will be called whenever an event
 comes in for that window.

 Note that for Unix and Mac the nsPluginEvent structure is different
 from the old NPEvent structure -- it's no longer the native event
 record, but is instead a struct. This was done for future extensibility,
 and so that the Mac could receive the window argument too. For Windows
 and OS2, it's always been a struct, so there's no change for them.

 (Corresponds to NPP_HandleEvent.)

 @param aEvent   - the event to be handled
 @param aHandled - set to PR_TRUE if event was handled
 @result - NS_OK if this operation was successful

void handleEvent(in nsPluginEventPtr aEvent, out boolean aHandled)

 Initializes a newly created plugin instance, passing to it the
 plugin instance peer which it should use for all communication
 back to the browser.
 
 @param aPeer - the corresponding plugin instance peer
 @result      - NS_OK if this operation was successful

void initialize(in nsIPluginInstancePeer aPeer)

 Called to tell the plugin that the initial src/data stream is
 ready.  Expects the plugin to return a nsIPluginStreamListener.

 (Corresponds to NPP_NewStream.)

 @param aListener - listener the browser will use to give the plugin the data
 @result          - NS_OK if this operation was successful

void newStream(out nsIPluginStreamListener aListener)

 Called to instruct the plugin instance to print itself to a printer.

 (Corresponds to NPP_Print.)

 @param aPlatformPrint - platform-specific printing information
 @result               - NS_OK if this operation was successful

void print(in nsPluginPrintPtr aPlatformPrint)

 Called when the window containing the plugin instance changes.

 (Corresponds to NPP_SetWindow.)

 @param aWindow - the plugin window structure
 @result        - NS_OK if this operation was successful

void setWindow(in nsPluginWindowPtr aWindow)

 Called to instruct the plugin instance to start. This will be
 called after the plugin is first created and initialized, and
 may be called after the plugin is stopped (via the Stop method)
 if the plugin instance is returned to in the browser window's
 history.

 @result - NS_OK if this operation was successful

void start()

 Called to instruct the plugin instance to stop, thereby
 suspending its state.  This method will be called whenever the
 browser window goes on to display another page and the page
 containing the plugin goes into the window's history list.

 @result - NS_OK if this operation was successful

void stop()