Emit a console warning when blocking event listener is delayed for too long

third_party/WebKit/Source/core/inspector/InspectorInputAgent.cpp

Index: third_party/WebKit/Source/core/inspector/InspectorInputAgent.cpp
diff --git a/third_party/WebKit/Source/core/inspector/InspectorInputAgent.cpp b/third_party/WebKit/Source/core/inspector/InspectorInputAgent.cpp
index 1fe3e8cb546a0153fa4808ee6db2fcf228984562..1ee5812883ccf3ef43069a9606b48fa0d6f53c38 100644
--- a/third_party/WebKit/Source/core/inspector/InspectorInputAgent.cpp
+++ b/third_party/WebKit/Source/core/inspector/InspectorInputAgent.cpp
@@ -30,8 +30,11 @@
 
 #include "core/inspector/InspectorInputAgent.h"
 
+#include "core/dom/ExecutionContext.h"
+#include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
+#include "core/frame/Settings.h"
 #include "core/input/EventHandler.h"
 #include "core/inspector/InspectedFrames.h"
 #include "core/page/ChromeClient.h"
@@ -124,6 +127,10 @@ void ConvertInspectorPoint(blink::LocalFrame* frame, const blink::IntPoint& poin
 
 namespace blink {
 
+namespace InputAgentState {
+static const char blockedEventsWarningThreshold[] = "blockedEventsWarningThreshold";
+}
+
 InspectorInputAgent::InspectorInputAgent(InspectedFrames* inspectedFrames)
     : InspectorBaseAgent<InspectorInputAgent, protocol::Frontend::Input>("Input")
     , m_inspectedFrames(inspectedFrames)
@@ -203,6 +210,22 @@ void InspectorInputAgent::dispatchTouchEvent(ErrorString* error, const String& t
     m_inspectedFrames->root()->eventHandler().handleTouchEvent(event);
 }
 
+void InspectorInputAgent::restore()
+{
+    ErrorString dummy;
+
+    setBlockedEventsWarningThreshold(&dummy, m_state->numberProperty(InputAgentState::blockedEventsWarningThreshold, 0.0));
+}
+
+void InspectorInputAgent::setBlockedEventsWarningThreshold(ErrorString*, double threshold)
+{
+    m_state->setNumber(InputAgentState::blockedEventsWarningThreshold, threshold);
+    FrameHost* host = m_inspectedFrames->root()->host();
+    if (!host)
+        return;
+    host->settings().setBlockedMainThreadEventsWarningThreshold(threshold);
+}
+
 DEFINE_TRACE(InspectorInputAgent)
 {
     visitor->trace(m_inspectedFrames);