Enable the IAT patcher unittests in x64.

syzygy/pe/pe.gyp

Index: syzygy/pe/pe.gyp
diff --git a/syzygy/pe/pe.gyp b/syzygy/pe/pe.gyp
index 201b2fa10ce3439cee43801f4484980f9efdcab9..2b2fb3f9db878300d7ee8ca096a42e855f8a114c 100644
--- a/syzygy/pe/pe.gyp
+++ b/syzygy/pe/pe.gyp
@@ -378,6 +378,7 @@
         'test_dll_x64.rc',
       ],
       'dependencies': [
+        'export_dll_x64',
         '<(src)/syzygy/version/version.gyp:syzygy_version',
       ],
       'msvs_settings': {
@@ -505,6 +506,30 @@
       },
     },
     {
+      'target_name': 'export_dll_x64',
+      'type': 'shared_library',
+      'sources': [
+        'export_dll.cc',
+        'export_dll_x64.def',
+      ],
+      'msvs_settings': {
+      },
+      'configurations': {
+        'Common_Base': {
+          'msvs_settings': {
+            'VCLinkerTool': {
+              'VCLinkerTool': {
+                # Force MSVS to produce the same output name as Ninja.
+                'ImportLibrary': '$(OutDir)lib\$(TargetFileName).lib'
+              },
+            },
+          },
+          'msvs_target_platform': 'x64',
+          'msvs_configuration_platform': 'x64',
+        },
+      },
+    },
+    {
       'target_name': 'decompose_image_to_text',
       'type': 'executable',
       'sources': [