errors reported running drmemory under drmemory

_From [bruen...@google.com](https://code.google.com/u/109494838902877177630/) on March 18, 2014 11:17:40_

A user pointed these out: http://pastebin.com/U5iUKBk8 % ~/drmemory/releases/DrMemory-Windows-1.6.1-2/bin/drmemory.exe -batch -- bin/drmemory.exe -dr d:/derek/dr/git/exports -- tests/hello.exe

With symbols the uninit is shown to be fields of CONTEXT not selected by ContextFlags (but perhaps the code should do extra verification that ContextFlags is what it expects):

~~Dr.M~~ Error `#1`: UNINITIALIZED READ: reading 0x002fdb08-0x002fdb18 16 byte(s) within 0x002fda78-0x002fdbc0
~~Dr.M~~ # 0 system call NtWriteVirtualMemory parameter `#2`
~~Dr.M~~ # 1 drinjectlib.dll!nt_write_virtual_memory [d:\derek\dr\git\src\core\win32\ntdll.c:2165]
~~Dr.M~~ # 2 drinjectlib.dll!inject_into_thread [d:\derek\dr\git\src\core\win32\inject.c:274]
~~Dr.M~~ # 3 drinjectlib.dll!dr_inject_process_inject [d:\derek\dr\git\src\core\win32\injector.c:874]
~~Dr.M~~ # 4 wmain [d:\derek\drmemory\git\src\drmemory\frontend.c:1623]
~~Dr.M~~ Note: @0:00:01.560 in thread 7004
~~Dr.M~~ Dr. Memory version 1.6.1780
~~Dr.M~~ Running "tests/hello.exe"

The leak needs investigation with better symbols.

_Original issue: http://code.google.com/p/drmemory/issues/detail?id=1479_