Install httpd-php to third_party/apache_mac

Also set up the path to httpd and config file properly.

We continue to use system httpd for mac10.12 and mac10.13,
as the 3pp htppd is built targeting newer version of Mac.

Bug: 1190885
Change-Id: If1e5264d26bcf384cb02e23facbd09fc9b33a2a8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3524265
Reviewed-by: Nico Weber <[email protected]>
Commit-Queue: Weizhong Xia <[email protected]>
Cr-Commit-Position: refs/heads/main@{#981444}
diff --git a/BUILD.gn b/BUILD.gn
index 45b4b53b..f686fc6 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1187,6 +1187,10 @@
       data_deps += [ "//build/win:copy_cdb_to_output" ]
     }
 
+    if (is_mac) {
+      data += [ "//third_party/apache-mac/" ]
+    }
+
     if (is_android) {
       data += [
         "//third_party/catapult/",