Fix pointer truncation in 64-bit Windows builds

This was found through a VC++ 2015 Update 1 warning about
pointer truncation. The fix is required for VC++ 2015
compatibility.

Review URL: https://codereview.chromium.org/1411403011

Cr-Commit-Position: refs/heads/master@{#31897}

src/base/platform/platform-win32.cc

@@ -1146,9 +1146,9 @@ static std::vector<OS::SharedLibraryAddress> LoadSymbols(
     WideCharToMultiByte(CP_UTF8, 0, module_entry.szExePath, -1, &lib_name[0],
                         lib_name_length, NULL, NULL);
     result.push_back(OS::SharedLibraryAddress(
-        lib_name, reinterpret_cast<unsigned int>(module_entry.modBaseAddr),
-        reinterpret_cast<unsigned int>(module_entry.modBaseAddr +
-                                       module_entry.modBaseSize)));
+        lib_name, reinterpret_cast<uintptr_t>(module_entry.modBaseAddr),
+        reinterpret_cast<uintptr_t>(module_entry.modBaseAddr +
+                                    module_entry.modBaseSize)));
     cont = _Module32NextW(snapshot, &module_entry);
   }
   CloseHandle(snapshot);