systray: Avoid modifying non-existent tooltip windows of non-existent icon windows when application updates tip of hidden icon.

shell32: Memory allocated by CommandLineToArgvW should be that got from LocalAlloc/LocalReAlloc, not from GlobalAlloc.

Use LMEM_FIXED instead of 0 in calls to LocalAlloc to emphasise that 
we're getting a direct pointer, not a handle to memory.

Remove hargv as it is confusing and unnecessary.

shlwapi: IID_IInternetSecurityMgrSite is now defined so remove the local definition from IUnknown_GetWindow.

dxdiagn: Fix the character count passed to snprintfW in DXDiag_AddFileDescContainer and DXDiag_InitDXDiagDisplayContainer.

dbghelp: Fix a typo in SymLoadModuleExW that caused the wrong number of characters to be passed to lstrcpynW.

advapi32: The lpcbSecurityDescriptor parameter to RegGetKeySecurity isn't optional, so don't complicate the code by treating as though it is.

This reverts commit 31876695.

Change the return value from BOOL to NTSTATUS so that we can return the 
exception code to the caller.