Update from https://crrev.com/309415

base/json/json_value_converter.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.
 
 #ifndef BASE_JSON_JSON_VALUE_CONVERTER_H_
 #define BASE_JSON_JSON_VALUE_CONVERTER_H_
 
 #include <string>
 #include <vector>
 
+#include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/stl_util.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_piece.h"
 #include "base/values.h"
 
 // JSONValueConverter converts a JSON value into a C++ struct in a
@@ skipping 109 matching lines @@
  private:
   FieldType StructType::* field_pointer_;
   scoped_ptr<ValueConverter<FieldType> > value_converter_;
   DISALLOW_COPY_AND_ASSIGN(FieldConverter);
 };
 
 template <typename FieldType>
 class BasicValueConverter;
 
 template <>
-class BasicValueConverter<int> : public ValueConverter<int> {
+class BASE_EXPORT BasicValueConverter<int> : public ValueConverter<int> {
  public:
   BasicValueConverter() {}
 
-  virtual bool Convert(const base::Value& value, int* field) const override {
-    return value.GetAsInteger(field);
-  }
+  bool Convert(const base::Value& value, int* field) const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BasicValueConverter);
 };
 
 template <>
-class BasicValueConverter<std::string> : public ValueConverter<std::string> {
+class BASE_EXPORT BasicValueConverter<std::string>
+    : public ValueConverter<std::string> {
  public:
   BasicValueConverter() {}
 
-  virtual bool Convert(
-      const base::Value& value, std::string* field) const override {
-    return value.GetAsString(field);
-  }
+  bool Convert(const base::Value& value, std::string* field) const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BasicValueConverter);
 };
 
 template <>
-class BasicValueConverter<string16> : public ValueConverter<string16> {
+class BASE_EXPORT BasicValueConverter<string16>
+    : public ValueConverter<string16> {
  public:
   BasicValueConverter() {}
 
-  virtual bool Convert(
-      const base::Value& value, string16* field) const override {
-    return value.GetAsString(field);
-  }
+  bool Convert(const base::Value& value, string16* field) const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BasicValueConverter);
 };
 
 template <>
-class BasicValueConverter<double> : public ValueConverter<double> {
+class BASE_EXPORT BasicValueConverter<double> : public ValueConverter<double> {
  public:
   BasicValueConverter() {}
 
-  virtual bool Convert(const base::Value& value, double* field) const override {
-    return value.GetAsDouble(field);
-  }
+  bool Convert(const base::Value& value, double* field) const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BasicValueConverter);
 };
 
 template <>
-class BasicValueConverter<bool> : public ValueConverter<bool> {
+class BASE_EXPORT BasicValueConverter<bool> : public ValueConverter<bool> {
  public:
   BasicValueConverter() {}
 
-  virtual bool Convert(const base::Value& value, bool* field) const override {
-    return value.GetAsBoolean(field);
-  }
+  bool Convert(const base::Value& value, bool* field) const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BasicValueConverter);
 };
 
 template <typename FieldType>
 class ValueFieldConverter : public ValueConverter<FieldType> {
  public:
   typedef bool(*ConvertFunc)(const base::Value* value, FieldType* field);
 
@@ skipping 307 matching lines @@
 
  private:
   ScopedVector<internal::FieldConverterBase<StructType> > fields_;
 
   DISALLOW_COPY_AND_ASSIGN(JSONValueConverter);
 };
 
 }  // namespace base
 
 #endif  // BASE_JSON_JSON_VALUE_CONVERTER_H_