Convert enable_plugins to a buildflag header.

content/browser/storage_partition_impl.cc

Index: content/browser/storage_partition_impl.cc
diff --git a/content/browser/storage_partition_impl.cc b/content/browser/storage_partition_impl.cc
index 8d03ebcf7b1be939163003648ceb4b64d6d3f259..0640453289ffc9f89ed3a80bb8b3ac70f98aab16 100644
--- a/content/browser/storage_partition_impl.cc
+++ b/content/browser/storage_partition_impl.cc
@@ -32,12 +32,13 @@
 #include "net/cookies/cookie_monster.h"
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_getter.h"
+#include "ppapi/features/features.h"
 #include "storage/browser/database/database_tracker.h"
 #include "storage/browser/quota/quota_manager.h"
 
-#if defined(ENABLE_PLUGINS)
+#if BUILDFLAG(ENABLE_PLUGINS)
 #include "content/browser/plugin_private_storage_helper.h"
-#endif  // defined(ENABLE_PLUGINS)
+#endif  // BUILDFLAG(ENABLE_PLUGINS)
 
 namespace content {
 
@@ -847,7 +848,7 @@ void StoragePartitionImpl::DataDeletionHelper::ClearDataOnUIThread(
                    path, begin, end, decrement_callback));
   }
 
-#if defined(ENABLE_PLUGINS)
+#if BUILDFLAG(ENABLE_PLUGINS)
   if (remove_mask & REMOVE_DATA_MASK_PLUGIN_PRIVATE_DATA) {
     IncrementTaskCountOnUI();
     filesystem_context->default_file_task_runner()->PostTask(
@@ -855,7 +856,7 @@ void StoragePartitionImpl::DataDeletionHelper::ClearDataOnUIThread(
                               make_scoped_refptr(filesystem_context),
                               storage_origin, begin, end, decrement_callback));
   }
-#endif  // defined(ENABLE_PLUGINS)
+#endif  // BUILDFLAG(ENABLE_PLUGINS)
 
   DecrementTaskCountOnUI();
 }