Fix truncation warning in PEImage on VS2015

d:\src\cr3\src\base\win\pe_image.h(250): error C2220: warning treated as error - no 'object' file generated
d:\src\cr3\src\base\win\pe_image.h(250): warning C4302: 'reinterpret_cast': truncation from 'LPCSTR' to 'WORD'

Separate ptr->int from truncation to WORD.

Also, while we're here, fix a cast in IsOrdinal.

R=cpu@chromium.org
BUG=440500

Review URL: https://codereview.chromium.org/883873002

Cr-Commit-Position: refs/heads/master@{#313543}

base/win/pe_image.h

@@ -239,15 +239,11 @@ class PEImageAsData : public PEImage {
 };
 
 inline bool PEImage::IsOrdinal(LPCSTR name) {
-#pragma warning(push)
-#pragma warning(disable: 4311)
-  // This cast generates a warning because it is 32 bit specific.
-  return reinterpret_cast<DWORD>(name) <= 0xFFFF;
-#pragma warning(pop)
+  return reinterpret_cast<uintptr_t>(name) <= 0xFFFF;
 }
 
 inline WORD PEImage::ToOrdinal(LPCSTR name) {
-  return reinterpret_cast<WORD>(name);
+  return static_cast<WORD>(reinterpret_cast<intptr_t>(name));
 }
 
 inline HMODULE PEImage::module() const {