Clear cache before running the test

third_party/WebKit/LayoutTests/http/tests/inspector/network-test.js

 // This goes before everything else to keep console message line number invariant.
 var lastXHRIndex = 0;
 function xhrLoadedCallback()
 {
     // We need to make sure the console message text is unique so that we don't end up with repeat count update only.
     console.log("XHR loaded: " + (++lastXHRIndex));
 }
 
 function makeSimpleXHR(method, url, async, callback)
 {
@@ skipping 30 matching lines @@
 {
     var args = JSON.parse(jsonArgs);
     makeXHR(args.method, args.url, args.async, args.user, args.password, args.headers || [], args.withCredentials, args.payload, args.type, xhrLoadedCallback);
 }
 
 function makeFetch(url, requestInitializer)
 {
     return fetch(url, requestInitializer).catch(e => e);
 }
 
+function onCacheStorageError(e)
+{
+    console.error("CacheStorage error: " + e);
+}
+
+function clearAllCaches()
+{
+    return caches.keys()
+        .then((keys) => Promise.all(keys.map((key) => caches.delete(key))))

[allada, 2016/12/15 19:01:49]

I see you pulled this from
http/tests/inspector/cache-storage/cache-storage-test.js, however I believe this
is for the cache storage api not the browser cache.

+        .catch(onCacheStorageError.bind(this));
+}
+
 var initialize_NetworkTest = function() {
 
 InspectorTest.preloadPanel("network");
 
 InspectorTest.recordNetwork = function()
 {
     UI.panels.network._networkLogView.setRecording(true);
 }
 
 InspectorTest.networkRequests = function()
@@ skipping 52 matching lines @@
 
     InspectorTest.addConsoleSniffer(innerCallback);
     InspectorTest.evaluateInPage("makeXHRForJSONArguments(\"" + jsonArgs + "\")");
 }
 
 InspectorTest.makeFetch = function(url, requestInitializer, callback)
 {
     InspectorTest.callFunctionInPageAsync("makeFetch", [url, requestInitializer]).then(callback);
 }
 
+InspectorTest.clearAllCaches = function()
+{
+    return InspectorTest.evaluateInPage("clearAllCaches");
+}
+
 InspectorTest.HARPropertyFormatters = {
     bodySize: "formatAsTypeName",
     compression: "formatAsTypeName",
     connection: "formatAsTypeName",
     headers: "formatAsTypeName",
     headersSize: "formatAsTypeName",
     id: "formatAsTypeName",
     onContentLoad: "formatAsTypeName",
     onLoad: "formatAsTypeName",
     receive: "formatAsTypeName",
     startedDateTime: "formatAsRecentTime",
     time: "formatAsTypeName",
     timings: "formatAsTypeName",
     version: "formatAsTypeName",
     wait: "formatAsTypeName",
     _transferSize: "formatAsTypeName",
     _error: "skip"
 };
 // addObject checks own properties only, so make a deep copy rather than use prototype.
 InspectorTest.HARPropertyFormattersWithSize = JSON.parse(JSON.stringify(InspectorTest.HARPropertyFormatters));
 InspectorTest.HARPropertyFormattersWithSize.size = "formatAsTypeName";
 
 };