Use base::StartWith() in more places when appropriate.

components/data_reduction_proxy/core/common/data_reduction_proxy_params.h

Index: components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
diff --git a/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h b/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
index 57d4affe96cd4e189476dd65c81e518250a2282e..a1df40adbb5e23dc95de5ff88505dd7582699c7c 100644
--- a/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
+++ b/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
@@ -2,13 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_PARAMS_H_
-#define COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_PARAMS_H_
+#ifndef COMPONENTS_DATA_REDUCTION_PROXY_CORE_COMMON_DATA_REDUCTION_PROXY_PARAMS_H_
+#define COMPONENTS_DATA_REDUCTION_PROXY_CORE_COMMON_DATA_REDUCTION_PROXY_PARAMS_H_
 
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
+#include "base/strings/string_piece.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_config_values.h"
 #include "net/proxy/proxy_server.h"
 #include "url/gurl.h"
@@ -49,7 +50,7 @@ bool IsIncludedInTrustedSpdyProxyFieldTrial();
 
 // Returns true if this client is part of the field trial that should display
 // a promotion for the data reduction proxy on Android One devices.
-bool IsIncludedInAndroidOnePromoFieldTrial(const char* build_fingerprint);
+bool IsIncludedInAndroidOnePromoFieldTrial(base::StringPiece build_fingerprint);
 
 // Returns the name of the Lo-Fi field trial.
 const char* GetLoFiFieldTrialName();
@@ -252,4 +253,5 @@ class DataReductionProxyParams : public DataReductionProxyConfigValues {
 };
 
 }  // namespace data_reduction_proxy
-#endif  // COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_PARAMS_H_
+
+#endif  // COMPONENTS_DATA_REDUCTION_PROXY_CORE_COMMON_DATA_REDUCTION_PROXY_PARAMS_H_