More windows fixes.

appveyor.yml

@@ -1,5 +1,5 @@
 version: 1.0.{build}
-image: Previous Visual Studio 2017
+image: Visual Studio 2017
 
 environment:
   CCACHE_DIR: "%APPVEYOR_BUILD_FOLDER%\\.ccache"

python/servo/command_base.py

@@ -575,7 +575,7 @@ install them, let us know by filing a bug!")
                 return path.join(msvc_deps_dir, package, msvc_deps[package])
 
             extra_path += [path.join(package_dir("cmake"), "bin")]
-            extra_path += [path.join(package_dir("llvm"), "bin")]
+            #extra_path += [path.join(package_dir("llvm"), "bin")]
             extra_path += [path.join(package_dir("ninja"), "bin")]
             # Link openssl
             env["OPENSSL_INCLUDE_DIR"] = path.join(package_dir("openssl"), "include")
@@ -589,7 +589,7 @@ install them, let us know by filing a bug!")
             # Link autoconf 2.13, used for building SpiderMonkey
             env["AUTOCONF"] = path.join(package_dir("moztools"), "msys", "local", "bin", "autoconf-2.13")
             # Link LLVM
-            env["LIBCLANG_PATH"] = path.join(package_dir("llvm"), "lib")
+            #env["LIBCLANG_PATH"] = path.join(package_dir("llvm"), "lib")
 
             if not os.environ.get("NATIVE_WIN32_PYTHON"):
                 env["NATIVE_WIN32_PYTHON"] = sys.executable

python/servo/packages.py

@@ -4,7 +4,6 @@
 
 WINDOWS_MSVC = {
     "cmake": "3.7.2",
-    "llvm": "6.0.0",
     "moztools": "3.2",
     "ninja": "1.7.1",
     "openssl": "1.1.0e-vs2015",