Cleanup: Fix content header include guards.

content/renderer/pepper/host_array_buffer_var.h

Index: content/renderer/pepper/host_array_buffer_var.h
diff --git a/content/renderer/pepper/host_array_buffer_var.h b/content/renderer/pepper/host_array_buffer_var.h
index fedca65d2c6c0fd9b2e459ae7aaf2c2a6c8273a6..3f917d46cd42283457c690c4846a13c6009c5299 100644
--- a/content/renderer/pepper/host_array_buffer_var.h
+++ b/content/renderer/pepper/host_array_buffer_var.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef PPAPI_CONTENT_RENDERER_PEPPER_HOST_ARRAY_BUFFER_VAR_H_
-#define PPAPI_CONTENT_RENDERER_PEPPER_HOST_ARRAY_BUFFER_VAR_H_
+#ifndef CONTENT_RENDERER_PEPPER_HOST_ARRAY_BUFFER_VAR_H_
+#define CONTENT_RENDERER_PEPPER_HOST_ARRAY_BUFFER_VAR_H_
 
 #include "base/memory/shared_memory.h"
 #include "ppapi/c/pp_instance.h"
@@ -43,4 +43,4 @@ class HostArrayBufferVar : public ppapi::ArrayBufferVar {
 
 }  // namespace content
 
-#endif  // PPAPI_CONTENT_RENDERER_PEPPER_HOST_ARRAY_BUFFER_VAR_H_
+#endif  // CONTENT_RENDERER_PEPPER_HOST_ARRAY_BUFFER_VAR_H_