Reland: Add trace event Pepper API

ppapi/c/dev/ppb_trace_event_dev.h

+/* Copyright (c) 2012 The Chromium Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* From dev/ppb_trace_event_dev.idl modified Wed Jan  2 16:11:35 2013. */
+
+#ifndef PPAPI_C_DEV_PPB_TRACE_EVENT_DEV_H_
+#define PPAPI_C_DEV_PPB_TRACE_EVENT_DEV_H_
+
+#include "ppapi/c/pp_macros.h"
+#include "ppapi/c/pp_stdint.h"
+
+#define PPB_TRACE_EVENT_DEV_INTERFACE_0_1 "PPB_Trace_Event(Dev);0.1"
+#define PPB_TRACE_EVENT_DEV_INTERFACE PPB_TRACE_EVENT_DEV_INTERFACE_0_1
+
+/**
+ * @file
+ * This file defines the <code>PPB_Trace_Event</code> interface. It is meant
+ * to be used in plugins as the API that trace macros from trace_event.h use.
+ */
+
+
+/**
+ * @addtogroup Interfaces
+ * @{
+ */
+struct PPB_Trace_Event_Dev_0_1 {
+  /**
+   * Gets a pointer to a character for identifying a category name in the
+   * tracing system as well as for being able to early exit in client-side
+   * tracing code.
+   *
+   * NB: This mem_t return value should technically be const, but return values
+   * for Pepper IDL of mem_t type are not const.  The same is true for the arg
+   * |category_enabled| for AddTraceEvent.
+   */
+  void* (*GetCategoryEnabled)(const char* category_name);
+  /**
+   * Adds a trace event to the platform tracing system. This function call is
+   * usually the result of a TRACE_* macro from trace_event.h when tracing and
+   * the category of the particular trace are enabled. It is not advisable to
+   * call this function on its own; it is really only meant to be used by the
+   * trace macros.
+   */
+  void (*AddTraceEvent)(int8_t phase,
+                        const void* category_enabled,
+                        const char* name,
+                        uint64_t id,
+                        uint32_t num_args,
+                        const char* arg_names[],
+                        const uint8_t arg_types[],
+                        const uint64_t arg_values[],
+                        uint8_t flags);
+  /**
+   * Sets the thread name of the calling thread in the tracing system so it will
+   * show up properly in chrome://tracing.
+   */
+  void (*SetThreadName)(const char* thread_name);
+};
+
+typedef struct PPB_Trace_Event_Dev_0_1 PPB_Trace_Event_Dev;
+/**
+ * @}
+ */
+
+#endif  /* PPAPI_C_DEV_PPB_TRACE_EVENT_DEV_H_ */
+