windows: look for new freeze_importlib content first

This line changed on Python 3.8. Let's look for the new line
first and fall back to the old search string on failure.

With this change, we can now actually start building Python
3.8. But a failure occurs during the build process.

Author: indygreg

cpython-windows/build.py

@@ -861,9 +861,18 @@ def hack_project_files(
     # Ditto for freeze_importlib, which isn't needed since we don't modify
     # the frozen importlib baked into the source distribution (
     # Python/importlib.h and Python/importlib_external.h).
-    static_replace_in_file(
-        pcbuild_proj, b'<Projects2 Include="_freeze_importlib.vcxproj" />', b""
-    )
+    try:
+        # Python 3.8.
+        static_replace_in_file(
+            pcbuild_proj,
+            b"""<Projects2 Condition="$(Platform) != 'ARM' and $(Platform) != 'ARM64'" Include="_freeze_importlib.vcxproj" />""",
+            b"",
+        )
+    except NoSearchStringError:
+        # Python 3.7.
+        static_replace_in_file(
+            pcbuild_proj, b'<Projects2 Include="_freeze_importlib.vcxproj" />', b""
+        )
 
 
 PYPORT_EXPORT_SEARCH = b"""