[tracing] Introduce BACKGROUND mode in MemoryInfra

base/trace_event/trace_config_memory_test_util.h

 // Copyright 2015 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.
 
 #ifndef BASE_TRACE_EVENT_TRACE_CONFIG_MEMORY_TEST_UTIL_H_
 #define BASE_TRACE_EVENT_TRACE_CONFIG_MEMORY_TEST_UTIL_H_
 
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/memory_dump_manager.h"
 
@@ skipping 53 matching lines @@
         "{"
           "\"enable_argument_filter\":false,"
           "\"enable_sampling\":false,"
           "\"enable_systrace\":false,"
           "\"included_categories\":["
             "\"%s\""
           "],"
           "\"record_mode\":\"record-until-full\""
         "}", MemoryDumpManager::kTraceCategory);
   }
+
+  static std::string GetTraceConfig_BackgroundTrigger() {
+    return StringPrintf(
+        "{"
+          "\"enable_argument_filter\":false,"
+          "\"enable_sampling\":false,"
+          "\"enable_systrace\":false,"
+          "\"included_categories\":["
+            "\"%s\""
+          "],"
+          "\"memory_dump_config\":{"
+             "\"triggers\":["
+              "{"
+                "\"mode\":\"background\","
+                "\"periodic_interval_ms\":1"
+              "}"
+            "]"
+          "},"
+          "\"record_mode\":\"record-until-full\""
+        "}", MemoryDumpManager::kTraceCategory);
+  }
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_TRACE_CONFIG_MEMORY_TEST_UTIL_H_