Match the ImmSetConversionStatus() function.

quartz: Make wave parser and mpeg splitter zero copy by getting rid of the seperate allocator for the output pin.

winhelp: Fix the loading of a row in a table (especially, for multiple paragraphs in a single cell).

winhelp: Added the notion of WINHELP_WNDPAGE and use it to move the history to the global variables.

winhelp: Get rid of the reuse concept for Windows and refactor the code a bit for window creation / deletion.