Move nacl targets to subdirectories.

This clarifies the structure a bit and is the format recommended by GN style.

Adds annotations to the GYP files for the corresponding GN targets. Removes some dead code in extensions/shell.

[email protected]
[email protected] (chrome/linux/installer)

Reland of https://codereview.chromium.org/1523503002

Review URL: https://codereview.chromium.org/1530663002

Cr-Commit-Position: refs/heads/master@{#365406}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index 058be57..aecf2cac 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -478,7 +478,7 @@
   if (enable_nacl) {
     sources +=
         rebase_path(gypi_values.chrome_browser_nacl_sources, ".", "//chrome")
-    deps += [ "//components/nacl:nacl_browser" ]
+    deps += [ "//components/nacl/browser" ]
   }
 
   if (enable_configuration_policy) {