Start off the Content API by moving content::ContentRendererClient to content\public\renderer.BU...

content/content.gyp

Index: content/content.gyp
===================================================================
--- content/content.gyp	(revision 103561)
+++ content/content.gyp	(working copy)
@@ -9,6 +9,7 @@
   },
   'includes': [
     '../build/win_precompile.gypi',
+    'content_api.gypi',
     'content_shell.gypi',
     'content_tests.gypi',
   ],
@@ -28,6 +29,7 @@
       {'target_name': 'content',
        'type': 'none',
        'dependencies': [
+        'content_api',
         'content_app',
         'content_browser',
         'content_common',
@@ -39,6 +41,12 @@
         'content_worker',
        ],
       },
+      {'target_name': 'content_api',
+       'type': 'none',
+       'includes': [
+          'content_api.gypi',
+        ],
+      },
       {'target_name': 'content_app',
        'type': 'static_library',
        'includes': [
@@ -186,6 +194,7 @@
       {'target_name': 'content',
        'type': 'shared_library',
        'includes': [
+        'content_api.gypi',
         'content_app.gypi',
         'content_browser.gypi',
         'content_common.gypi',
@@ -197,6 +206,9 @@
         'content_worker.gypi',
        ],
       },
+      {'target_name': 'content_api',
+       'type': 'none',
+      },
       {'target_name': 'content_app',
        'type': 'none',
        'dependencies': ['content', 'content_browser'],