Export symbols for shared library build.

ppapi/shared_impl/proxy_lock.h

Index: ppapi/shared_impl/proxy_lock.h
diff --git a/ppapi/shared_impl/proxy_lock.h b/ppapi/shared_impl/proxy_lock.h
index aa6120ef90ff7587273c5f9c21d1db88f922ee80..cc90501d9400d17f362c221a0d6e5382253443e0 100644
--- a/ppapi/shared_impl/proxy_lock.h
+++ b/ppapi/shared_impl/proxy_lock.h
@@ -7,6 +7,8 @@
 
 #include "base/basictypes.h"
 
+#include "ppapi/shared_impl/ppapi_shared_export.h"
+
 namespace base {
 class Lock;
 }
@@ -21,7 +23,7 @@ namespace ppapi {
 // TODO(dmichael): If this turns out to be too slow and contentious, we'll want
 // to use multiple locks. E.g., one for the var tracker, one for the resource
 // tracker, etc.
-class ProxyLock {
+class PPAPI_SHARED_EXPORT ProxyLock {
  public:
   // Acquire the proxy lock. If it is currently held by another thread, block
   // until it is available. If the lock has not been set using the 'Set' method,