Adds the ability to load JSON log files to about:net-internals.

chrome/browser/resources/net_internals/dataview.js

Index: chrome/browser/resources/net_internals/dataview.js
===================================================================
--- chrome/browser/resources/net_internals/dataview.js	(revision 72508)
+++ chrome/browser/resources/net_internals/dataview.js	(working copy)
@@ -19,7 +19,12 @@
                   byteLoggingCheckboxId,
                   passivelyCapturedCountId,
                   activelyCapturedCountId,
-                  deleteAllId) {
+                  deleteAllId,
+                  dumpDataDivId,
+                  loadDataDivId,
+                  loadLogFileId,
+                  capturingTextSpanId,
+                  loggingTextSpanId) {
   DivView.call(this, mainBoxId);
 
   this.textPre_ = document.getElementById(outputTextBoxId);
@@ -40,6 +45,14 @@
   document.getElementById(deleteAllId).onclick =
       g_browser.deleteAllEvents.bind(g_browser);
 
+  this.dumpDataDiv_ = document.getElementById(dumpDataDivId);
+  this.loadDataDiv_ = document.getElementById(loadDataDivId);
+  this.capturingTextSpan_ = document.getElementById(capturingTextSpanId);
+  this.loggingTextSpan_ = document.getElementById(loggingTextSpanId);
+
+  document.getElementById(loadLogFileId).onclick =
+      g_browser.loadLogFile.bind(g_browser);
+
   this.updateEventCounts_();
   this.waitingForUpdate_ = false;
 
@@ -71,6 +84,18 @@
 };
 
 /**
+ * Called when either a log file is loaded or when going back to actively
+ * logging events.  In either case, called after clearing the old entries,
+ * but before getting any new ones.
+ */
+DataView.prototype.onSetIsViewingLogFile = function(isViewingLogFile) {
+  setNodeDisplay(this.dumpDataDiv_, !isViewingLogFile);
+  setNodeDisplay(this.capturingTextSpan_, !isViewingLogFile);
+  setNodeDisplay(this.loggingTextSpan_, isViewingLogFile);
+  this.setText_('');
+};
+
+/**
  * Updates the counters showing how many events have been captured.
  */
 DataView.prototype.updateEventCounts_ = function() {
@@ -108,6 +133,10 @@
  * Presents the captured data as formatted text.
  */
 DataView.prototype.onUpdateAllCompleted = function(data) {
+  // It's possible for a log file to be loaded while a dump is being generated.
+  // When that happens, don't display the log dump, to avoid any confusion.
+  if (g_browser.isViewingLogFile())
+    return;
   this.waitingForUpdate_ = false;
   var text = [];