2 files changed, 30 insertions, 2 deletions
diff --git a/chrome/renderer/resources/extensions/web_view_experimental.js b/chrome/renderer/resources/extensions/web_view_experimental.js
index 18862cd..923ed65 100644
--- a/chrome/renderer/resources/extensions/web_view_experimental.js
+++ b/chrome/renderer/resources/extensions/web_view_experimental.js
@@ -42,6 +42,10 @@ var ERROR_MSG_NEWWINDOW_ACTION_ALREADY_TAKEN = '<webview>: ' +
 /** @type {string} */
 var ERROR_MSG_WEBVIEW_EXPECTED = '<webview> element expected.';
 
+/** @type {string} */
+var ERROR_MSG_CANNOT_INJECT_SCRIPT = '<webview>: ' +
+    'Script cannot be injected into content until the page has loaded.';
+
 /**
  * @private
  */
@@ -113,14 +117,22 @@ WebView.prototype.setupPermissionEvent_ = function() {
  */
 WebView.prototype.setupExecuteCodeAPI_ = function() {
   var self = this;
+  var validateCall = function() {
+    if (!self.browserPluginNode_.getGuestInstanceId()) {
+      throw new Error(ERROR_MSG_CANNOT_INJECT_SCRIPT);
+    }
+  };
+
   this.webviewNode_['executeScript'] = function(var_args) {
+    validateCall();
     var args = [self.browserPluginNode_.getGuestInstanceId()].concat(
-                    Array.prototype.slice.call(arguments));
+        Array.prototype.slice.call(arguments));
     chrome.webview.executeScript.apply(null, args);
   }
   this.webviewNode_['insertCSS'] = function(var_args) {
+    validateCall();
     var args = [self.browserPluginNode_.getGuestInstanceId()].concat(
-                    Array.prototype.slice.call(arguments));
+        Array.prototype.slice.call(arguments));
     chrome.webview.insertCSS.apply(null, args);
   }
 };
diff --git a/chrome/test/data/extensions/platform_apps/web_view/shim/main.js b/chrome/test/data/extensions/platform_apps/web_view/shim/main.js
index a172e4d..9978a9b 100644
--- a/chrome/test/data/extensions/platform_apps/web_view/shim/main.js
+++ b/chrome/test/data/extensions/platform_apps/web_view/shim/main.js
@@ -212,6 +212,22 @@ chrome.test.getConfig(function(config) {
       }, 0);
     },
 
+    function webViewExecuteScriptFail() {
+      var webview = document.createElement('webview');
+      document.body.appendChild(webview);
+      setTimeout(function() {
+        try {
+        webview.executeScript(
+          {code:'document.body.style.backgroundColor = "red";'},
+          function(results) {
+            chrome.test.fail();
+          });
+        } catch (e) {
+          chrome.test.succeed();
+        }
+      }, 0);
+    },
+
     function webViewExecuteScript() {
       var webview = document.createElement('webview');
       webview.setAttribute('partition', arguments.callee.name);