GN: Build libvpx

* Changes the include order of YASM
Default includes need to be put to the end for YASM.

In particular there are several versions of x86inc.asm in the tree and
libvpx requires its own version. This change in order allows libvpx to
include its own version.

* Roll libvpx to include BUILD.gn.

libvpx now builds on x86 posix.

R=brettw@chromium.org, scherkus@chromium.org, tomfinegan@chromium.org

Review URL: https://codereview.chromium.org/535613002

Cr-Commit-Position: refs/heads/master@{#294932}

1 files changed, 14 insertions, 13 deletions

diff --git a/third_party/yasm/yasm_assemble.gni b/third_party/yasm/yasm_assemble.gni
index ed89829..92e99d1 100644
--- a/third_party/yasm/yasm_assemble.gni
+++ b/third_party/yasm/yasm_assemble.gni
@@ -81,18 +81,6 @@ if (is_mac || is_ios) {
   }
 }
 
-# Default yasm include dirs. Make it match the native build (source root and
-# root generated code directory).
-_yasm_flags += [
-  "-I.",
-  # Using "//." will produce a relative path "../.." which looks better than
-  # "../../" which will result from using "//" as the base (although both
-  # work). This is because rebase_path will terminate the result in a slash if
-  # the input ends in a slash.
-  "-I" + rebase_path("//.", root_build_dir),
-  "-I" + rebase_path(root_gen_dir, root_build_dir),
-]
-
 if (is_win) {
   asm_obj_extension = "obj"
 } else {
@@ -142,13 +130,26 @@ template("yasm_assemble") {
       args += invoker.yasm_flags
     }
 
-    # Extra include directories.
+    # User defined include dirs go first.
     if (defined(invoker.include_dirs)) {
       foreach(include, invoker.include_dirs) {
         args += [ "-I" + rebase_path(include, root_build_dir) ]
       }
     }
 
+    # Default yasm include dirs. Make it match the native build (source root and
+    # root generated code directory).
+    # This goes to the end of include list.
+    args += [
+      # Using "//." will produce a relative path "../.." which looks better than
+      # "../../" which will result from using "//" as the base (although both
+      # work). This is because rebase_path will terminate the result in a
+      # slash if the input ends in a slash.
+      "-I" + rebase_path("//.", root_build_dir),
+      "-I" + rebase_path(root_gen_dir, root_build_dir),
+    ]
+
+
     # Extra defines.
     if (defined(invoker.defines)) {
       foreach(def, invoker.defines) {