Split //ui/gl into //ui/gl + //ui/gi/init.

Refactor //ui/gl to fix Ozone dep problem. This CL is step 1 described
in the associated bug.

BUG=611142
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review-Url: https://codereview.chromium.org/1920163005
Cr-Commit-Position: refs/heads/master@{#393838}

diff --git a/ui/aura/BUILD.gn b/ui/aura/BUILD.gn
index 32e747d..99b3b1f 100644
--- a/ui/aura/BUILD.gn
+++ b/ui/aura/BUILD.gn

@@ -243,7 +243,7 @@
     "//ui/events",
     "//ui/gfx",
     "//ui/gfx/geometry",
-    "//ui/gl",
+    "//ui/gl/init",
   ]
 
   if (use_x11) {