A few tests initialized two GpGraphics objects, and only released one.
These have been fixed by removing the redundant initialization.

Used by IE7's Add On management dialog.

dbghelp: Simplify the resort operation (module address table) by using binary insertion instead of resorting the whole array.

dbghelp: when (re)building the per module symbol table (lookup by address), no longer iterate over the hash table.

Directly add to the table when adding a new symbol.

Based on a patch by Rob Shearman.