[DevTools] Move from InstrumentingAgents to InstrumentingSessions.

third_party/WebKit/Source/modules/accessibility/InspectorAccessibilityAgent.cpp

Index: third_party/WebKit/Source/modules/accessibility/InspectorAccessibilityAgent.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/InspectorAccessibilityAgent.cpp b/third_party/WebKit/Source/modules/accessibility/InspectorAccessibilityAgent.cpp
index 43f312c9de35142bba0e51292b53f3f48425eabb..138f07b1dacc5fdab8621ca0c05bd2b621c5edd7 100644
--- a/third_party/WebKit/Source/modules/accessibility/InspectorAccessibilityAgent.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/InspectorAccessibilityAgent.cpp
@@ -358,9 +358,10 @@ PassOwnPtr<AXNode> buildObjectForNode(Node* node, AXObject* axObject, AXObjectCa
 
 } // namespace
 
-InspectorAccessibilityAgent::InspectorAccessibilityAgent(Page* page)
+InspectorAccessibilityAgent::InspectorAccessibilityAgent(Page* page, InspectorDOMAgent* domAgent)
     : InspectorBaseAgent<InspectorAccessibilityAgent, protocol::Frontend::Accessibility>("Accessibility")
     , m_page(page)
+    , m_domAgent(domAgent)
 {
 }
 
@@ -372,12 +373,11 @@ void InspectorAccessibilityAgent::getAXNode(ErrorString* errorString, int nodeId
         return;
     }
 
-    InspectorDOMAgent* domAgent = toLocalFrame(mainFrame)->instrumentingAgents()->inspectorDOMAgent();
-    if (!domAgent) {
+    if (!m_domAgent->enabled()) {
         *errorString = "DOM agent must be enabled";
         return;
     }
-    Node* node = domAgent->assertNode(errorString, nodeId);
+    Node* node = m_domAgent->assertNode(errorString, nodeId);
     if (!node)
         return;
 
@@ -403,6 +403,7 @@ void InspectorAccessibilityAgent::getAXNode(ErrorString* errorString, int nodeId
 DEFINE_TRACE(InspectorAccessibilityAgent)
 {
     visitor->trace(m_page);
+    visitor->trace(m_domAgent);
     InspectorBaseAgent::trace(visitor);
 }