Mojo: Move mojo/public/shell to mojo/public/{cpp,interfaces}/shell.

mojo/mojo_public.gypi

 {
   'targets': [
     {
       'target_name': 'mojo_system',
       'type': 'shared_library',
       'defines': [
         'MOJO_SYSTEM_IMPLEMENTATION',
       ],
       'include_dirs': [
         '..',
@@ skipping 340 matching lines @@
         }],
       ],
       'include_dirs': [
         '..',
       ],
     },
     {
       'target_name': 'mojo_shell_bindings',
       'type': 'static_library',
       'sources': [
-        'public/shell/shell.mojom',
+        'public/interfaces/shell/shell.mojom',
       ],
       'variables': {
         'mojom_base_output_dir': 'mojo',
       },
       'includes': [ 'public/bindings/mojom_bindings_generator.gypi' ],
       'dependencies': [
         'mojo_bindings',
         'mojo_system',
       ],
       'export_dependent_settings': [
         'mojo_bindings',
       ],
     },
     {
       'target_name': 'mojo_shell_client',
       'type': 'static_library',
       'sources': [
-        'public/shell/lib/application.cc',
-        'public/shell/lib/service.cc',
-        'public/shell/application.h',
-        'public/shell/service.h',
+        'public/cpp/shell/application.h',
+        'public/cpp/shell/service.h',
+        'public/cpp/shell/lib/application.cc',
+        'public/cpp/shell/lib/service.cc',
       ],
       'dependencies': [
         'mojo_shell_bindings',
       ],
       'export_dependent_settings': [
         'mojo_shell_bindings',
       ],
     },
   ],
 }