Initial patch for the web modules layered platform proposal.

Source/core/core.gypi

Index: Source/core/core.gypi
diff --git a/Source/core/core.gypi b/Source/core/core.gypi
index 3e1498efcd88c2e2d819fa459451af3953b02fa3..76ba23146308b87288736fd8d1ae5ec801f72f19 100644
--- a/Source/core/core.gypi
+++ b/Source/core/core.gypi
@@ -3,6 +3,9 @@
         'core_generated.gypi',
     ],
     'variables': {
+        'core_web_modules_idl_files': [
+            'dom/Node.idl',

[haraken, 2016/07/30 15:35:02]

It's a bit unfortunate that we need to list up IDL files that have
[WebModulesExposed]. Can we generate the list automatically? (You don't need to
address in this CL though.)

+        ],
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/KeyframeEffect.idl',