Allow XHR timeout attribute to be overridden after send(), per spec

Source/core/loader/DocumentThreadableLoader.cpp

Index: Source/core/loader/DocumentThreadableLoader.cpp
diff --git a/Source/core/loader/DocumentThreadableLoader.cpp b/Source/core/loader/DocumentThreadableLoader.cpp
index 2840dce77f4d9e26c4eae1e3c59f20864f715df6..2fc71d221bcf3bd031caa1e44570aab008536ffe 100644
--- a/Source/core/loader/DocumentThreadableLoader.cpp
+++ b/Source/core/loader/DocumentThreadableLoader.cpp
@@ -76,11 +76,14 @@ DocumentThreadableLoader::DocumentThreadableLoader(Document& document, Threadabl
     , m_simpleRequest(true)
     , m_async(blockingBehavior == LoadAsynchronously)
     , m_timeoutTimer(this, &DocumentThreadableLoader::didTimeout)
+    , m_requestStarted(0.0)
 {
     ASSERT(client);
     // Setting an outgoing referer is only supported in the async code path.
     ASSERT(m_async || request.httpReferrer().isEmpty());
 
+    m_requestStarted = monotonicallyIncreasingTime();
+
     // Save any CORS simple headers on the request here. If this request redirects cross-origin, we cancel the old request
     // create a new one, and copy these headers.
     const HTTPHeaderMap& headerMap = request.httpHeaderFields();
@@ -138,6 +141,26 @@ DocumentThreadableLoader::~DocumentThreadableLoader()
 {
 }
 
+void DocumentThreadableLoader::overrideTimeout(unsigned long timeoutMilliseconds)
+{
+    if (!m_async)
+        return;
+    m_timeoutTimer.stop();
+    // At the time of this method's implementation, it is only ever called by
+    // XMLHttpRequest, when the timeout attribute is set after sending the
+    // request.
+    //
+    // The XHR request says to resolve the time relative to when the request
+    // was initially sent, however other uses of this method may need to
+    // behave differently, in which case this should be re-arranged somehow.
+    if (timeoutMilliseconds && m_requestStarted > 0.0) {
+        double elapsedTime = monotonicallyIncreasingTime() - m_requestStarted;
+        double nextFire = timeoutMilliseconds / 1000.0;
+        double resolvedTime = nextFire > elapsedTime ? nextFire - elapsedTime : 0.0;

[eseidel, 2014/05/21 21:41:50]

std:min(nextfire - elapsedTime, 0) may be simpler.

+        m_timeoutTimer.startOneShot(resolvedTime, FROM_HERE);
+    }
+}
+
 void DocumentThreadableLoader::cancel()
 {
     cancelWithError(ResourceError());
@@ -159,6 +182,7 @@ void DocumentThreadableLoader::cancelWithError(const ResourceError& error)
     }
     clearResource();
     m_client = 0;
+    m_requestStarted = 0.0;
 }
 
 void DocumentThreadableLoader::setDefersLoading(bool value)
@@ -337,6 +361,8 @@ void DocumentThreadableLoader::notifyFinished(Resource* resource)
         m_client->didFail(resource->resourceError());
     else
         didFinishLoading(resource->identifier(), resource->loadFinishTime());
+
+    m_requestStarted = 0.0;

[tyoshino (SeeGerritForStatus), 2014/05/28 02:21:26]

not here. see below

 }
 
 void DocumentThreadableLoader::didFinishLoading(unsigned long identifier, double finishTime)