Revert of Make ui gn check pass. Misc GN build improvements. (patchset #3 id:40001 of https://codereview.chromium.org/545313002/)

Reason for revert:
Broke http://build.chromium.org/p/chromium.linux/builders/Linux%20GN%20%28dbg%29/builds/11835

[783/786 | 258.324] LINK ./chrome
FAILED: /mnt/data/b/build/goma/gomacc ../../third_party/llvm-build/Release+Asserts/bin/clang++ -Wl,--fatal-warnings -m64 -fPIC -Wl,-z,noexecstack -Wl,-z,now -Wl,-z,relro -pthread -B../../third_party/binutils/Linux_x64/Release/bin -fuse-ld=gold -Wl,--icf=none -Wl,-rpath=\$ORIGIN/ -Wl,-rpath-link= -Wl,--disable-new-dtags -o ./keyboard_unittests -Wl,--start-group @./keyboard_unittests.rsp  -Wl,--end-group  -ldl -lgmodule-2.0 -lgobject-2.0 -lgthread-2.0 -lrt -lglib-2.0 -ludev -lfontconfig -lX11 -lXcomposite -lXcursor -lXdamage -lXext -lXfixes -lXi -lXrender -lXss -lXtst -lpangocairo-1.0 -lpango-1.0 -lcairo -lnss3 -lnssutil3 -lsmime3 -lplds4 -lplc4 -lnspr4 -lgconf-2 -lresolv -lfreetype -lasound -lXrandr -lcups -lgssapi_krb5 -lkrb5 -lk5crypto -lcom_err -lgcrypt -lz -lpthread -lcrypt -lm -lcap -ldbus-1 -lcrypto -lexpat
../../content/utility/utility_thread_impl.cc:38: error: undefined reference to 'content::UtilityThread::UtilityThread()'
../../content/utility/utility_thread_impl.cc:44: error: undefined reference to 'content::UtilityThread::UtilityThread()'
../../content/utility/utility_thread_impl.cc:49: error: undefined reference to 'content::UtilityThread::~UtilityThread()'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
ninja: build stopped: subcommand failed.

Original issue's description:
> Make ui gn check pass. Misc GN build improvements.
>
> Content/public/app was messed up and didn't link everything properly, so this separates it out into browser and child like content/app is.
>
> [email protected]
>
> Committed: https://chromium.googlesource.com/chromium/src/+/b41a8d6e789ac5df9a6d314cd0ad59f584f53dea

[email protected],[email protected]
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/546943003

Cr-Commit-Position: refs/heads/master@{#293595}
diff --git a/content/BUILD.gn b/content/BUILD.gn
index c59434b..b4eeb26 100644
--- a/content/BUILD.gn
+++ b/content/BUILD.gn
@@ -13,6 +13,7 @@
   "//content/gpu",
   "//content/plugin",
   "//content/ppapi_plugin",
+  "//content/public/app",
   "//content/public/browser:sources",
   "//content/public/child",
   "//content/public/common",
@@ -26,7 +27,6 @@
   shared_library("content") {
     deps = content_shared_components + [
       "//content/app",
-      "//content/public/app",
     ]
     forward_dependent_configs_from = deps
   }