http: remove legacy parser

Remove the legacy `http_parser` implementation as a dependency
and all code that uses it in favor of llhttp, given that the latter
has been the default for all of Node 12 with no outstanding issues.

LICENSE

@@ -114,29 +114,6 @@ The externally maintained libraries used by Node.js are:
     purpose.  It is provided "as is" without express or implied warranty.
   """
 
-- HTTP Parser, located at deps/http_parser, is licensed as follows:
-  """
-    Copyright Joyent, Inc. and other Node contributors.
-
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to
-    deal in the Software without restriction, including without limitation the
-    rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
-    sell copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
-
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
-
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
-    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
-    IN THE SOFTWARE.
-  """
-
 - ICU, located at deps/icu-small, is licensed as follows:
   """
     COPYRIGHT AND PERMISSION NOTICE (ICU 58 and later)

Makefile

@@ -141,7 +141,7 @@ test-code-cache: with-code-cache
 	echo "'test-code-cache' target is a noop"
 
 out/Makefile: config.gypi common.gypi node.gyp \
-	deps/uv/uv.gyp deps/http_parser/http_parser.gyp deps/zlib/zlib.gyp \
+	deps/uv/uv.gyp deps/llhttp/llhttp.gyp deps/zlib/zlib.gyp \
 	tools/v8_gypfiles/toolchain.gypi tools/v8_gypfiles/features.gypi \
 	tools/v8_gypfiles/inspector.gypi tools/v8_gypfiles/v8.gyp
 	$(PYTHON) tools/gyp_node.py -f make