Update HTTPHeaderMap wrappers to use AtomicString type for header values

Source/core/inspector/NetworkResourcesData.cpp

Index: Source/core/inspector/NetworkResourcesData.cpp
diff --git a/Source/core/inspector/NetworkResourcesData.cpp b/Source/core/inspector/NetworkResourcesData.cpp
index 0cd8d6832a1635a3be05a50c6748599cef4b34d2..3427421e4ac19dd97dae3109f4332539d708f223 100644
--- a/Source/core/inspector/NetworkResourcesData.cpp
+++ b/Source/core/inspector/NetworkResourcesData.cpp
@@ -45,17 +45,17 @@ static size_t maximumSingleResourceContentSize = 10 * 1000 * 1000;
 namespace WebCore {
 
 
-PassRefPtr<XHRReplayData> XHRReplayData::create(const String &method, const KURL& url, bool async, PassRefPtr<FormData> formData, bool includeCredentials)
+PassRefPtr<XHRReplayData> XHRReplayData::create(const AtomicString& method, const KURL& url, bool async, PassRefPtr<FormData> formData, bool includeCredentials)
 {
     return adoptRef(new XHRReplayData(method, url, async, formData, includeCredentials));
 }
 
-void XHRReplayData::addHeader(const AtomicString& key, const String& value)
+void XHRReplayData::addHeader(const AtomicString& key, const AtomicString& value)
 {
     m_headers.set(key, value);
 }
 
-XHRReplayData::XHRReplayData(const String &method, const KURL& url, bool async, PassRefPtr<FormData> formData, bool includeCredentials)
+XHRReplayData::XHRReplayData(const AtomicString& method, const KURL& url, bool async, PassRefPtr<FormData> formData, bool includeCredentials)
     : m_method(method)
     , m_url(url)
     , m_async(async)