Revert the part of r90660 that enables building ppapi examples on win.

ppapi/ppapi_tests.gypi

Index: ppapi/ppapi_tests.gypi
diff --git a/ppapi/ppapi_tests.gypi b/ppapi/ppapi_tests.gypi
index b1eab29d4a3e7e79e0441e6c80366b91e36405a5..ca09ebe7f962c9e1d8545eee186f28d87d946056 100644
--- a/ppapi/ppapi_tests.gypi
+++ b/ppapi/ppapi_tests.gypi
@@ -191,9 +191,14 @@
   ],
 
   'conditions': [
-    # NOTE: the PPAPI examples fail to build on mac.
+    # NOTE: the PPAPI examples fail to build on mac & windows.
     # http://code.google.com/p/chromium/issues/detail?id=54005 tracks mac.
-    ['OS!="mac"', {
+    # TODO(ppapi authors):  Make the examples build on Windows as well.  In
+    # particular previous attempts have failed because the Win(clobber) and
+    # WinShared(dbg) builds try to build all, import *.gyp:*, and "all" becomes
+    # a direct dependent of ppapi_example_skeleton, making it a shared_library,
+    # and confusing the build system into failure.
+    ['OS!="win" and OS!="mac"', {
       'targets': [
         {
           'target_name': 'ppapi_example_skeleton',