Disable 4 PDFExtensionTest test cases as they fail on multiple bots.

chrome/browser/pdf/pdf_extension_test.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 
 #include <vector>
 
 #include "base/base_paths.h"
 #include "base/files/file_enumerator.h"
@@ skipping 627 matching lines @@
     "          inlineTextBox '2'\n"
     "    region 'Page 3'\n"
     "      paragraph\n"
     "        staticText '2 Second Section\\r\\n'\n"
     "          inlineTextBox '2 '\n"
     "          inlineTextBox 'Second Section\\r\\n'\n"
     "      paragraph\n"
     "        staticText '3'\n"
     "          inlineTextBox '3'\n";
 
-IN_PROC_BROWSER_TEST_F(PDFExtensionTest, PdfAccessibility) {
+// https://crbug.com/701427
+IN_PROC_BROWSER_TEST_F(PDFExtensionTest, DISABLED_PdfAccessibility) {
   content::BrowserAccessibilityState::GetInstance()->EnableAccessibility();
 
   GURL test_pdf_url(embedded_test_server()->GetURL("/pdf/test-bookmarks.pdf"));
   content::WebContents* guest_contents = LoadPdfGetGuestContents(test_pdf_url);
   ASSERT_TRUE(guest_contents);
 
   WaitForAccessibilityTreeToContainNodeWithName(guest_contents,
                                                 "1 First Section\r\n");
   ui::AXTreeUpdate ax_tree = GetAccessibilityTreeSnapshot(guest_contents);
   std::string ax_tree_dump = DumpPdfAccessibilityTree(ax_tree);
   ASSERT_MULTILINE_STREQ(kExpectedPDFAXTree, ax_tree_dump);
 }
 
 #if defined(GOOGLE_CHROME_BUILD)
 // Test a particular PDF encountered in the wild that triggered a crash
 // when accessibility is enabled.  (http://crbug.com/648981)
 IN_PROC_BROWSER_TEST_F(PDFExtensionTest, PdfAccessibilityCharCountCrash) {
   content::BrowserAccessibilityState::GetInstance()->EnableAccessibility();
   GURL test_pdf_url(embedded_test_server()->GetURL(
       "/pdf_private/accessibility_crash_1.pdf"));
 
   content::WebContents* guest_contents = LoadPdfGetGuestContents(test_pdf_url);
   ASSERT_TRUE(guest_contents);
 
   WaitForAccessibilityTreeToContainNodeWithName(guest_contents, "Page 1");
 }
 #endif
 
-IN_PROC_BROWSER_TEST_F(PDFExtensionTest, PdfAccessibilityEnableLater) {
+// https://crbug.com/701427
+IN_PROC_BROWSER_TEST_F(PDFExtensionTest, DISABLED_PdfAccessibilityEnableLater) {
   // In this test, load the PDF file first, with accessibility off.
   GURL test_pdf_url(embedded_test_server()->GetURL("/pdf/test-bookmarks.pdf"));
   content::WebContents* guest_contents = LoadPdfGetGuestContents(test_pdf_url);
   ASSERT_TRUE(guest_contents);
 
   // Now enable accessibility globally, and assert that the PDF accessibility
   // tree loads.
   EnableAccessibilityForWebContents(guest_contents);
   WaitForAccessibilityTreeToContainNodeWithName(guest_contents,
                                                 "1 First Section\r\n");
   ui::AXTreeUpdate ax_tree = GetAccessibilityTreeSnapshot(guest_contents);
   std::string ax_tree_dump = DumpPdfAccessibilityTree(ax_tree);
   ASSERT_MULTILINE_STREQ(kExpectedPDFAXTree, ax_tree_dump);
 }
 
 bool RetrieveGuestContents(
     content::WebContents** out_guest_contents,
     content::WebContents* in_guest_contents) {
   *out_guest_contents = in_guest_contents;
   return true;
 }
 
-IN_PROC_BROWSER_TEST_F(PDFExtensionTest, PdfAccessibilityInIframe) {
+// https://crbug.com/701427
+IN_PROC_BROWSER_TEST_F(PDFExtensionTest, DISABLED_PdfAccessibilityInIframe) {
   content::BrowserAccessibilityState::GetInstance()->EnableAccessibility();
   GURL test_iframe_url(embedded_test_server()->GetURL("/pdf/test-iframe.html"));
   ui_test_utils::NavigateToURL(browser(), test_iframe_url);
   content::WebContents* contents =
       browser()->tab_strip_model()->GetActiveWebContents();
   WaitForAccessibilityTreeToContainNodeWithName(contents,
                                                 "1 First Section\r\n");
 
   content::WebContents* guest_contents = nullptr;
   content::BrowserPluginGuestManager* guest_manager =
         contents->GetBrowserContext()->GetGuestManager();
   guest_manager->ForEachGuest(contents,
                               base::Bind(&RetrieveGuestContents,
                                          &guest_contents));
   ASSERT_TRUE(guest_contents);
 
   ui::AXTreeUpdate ax_tree = GetAccessibilityTreeSnapshot(guest_contents);
   std::string ax_tree_dump = DumpPdfAccessibilityTree(ax_tree);
   ASSERT_MULTILINE_STREQ(kExpectedPDFAXTree, ax_tree_dump);
 }
 
-IN_PROC_BROWSER_TEST_F(PDFExtensionTest, PdfAccessibilityInOOPIF) {
+// https://crbug.com/701427
+IN_PROC_BROWSER_TEST_F(PDFExtensionTest, DISABLED_PdfAccessibilityInOOPIF) {
   content::BrowserAccessibilityState::GetInstance()->EnableAccessibility();
   GURL test_iframe_url(embedded_test_server()->GetURL(
       "/pdf/test-cross-site-iframe.html"));
   ui_test_utils::NavigateToURL(browser(), test_iframe_url);
   content::WebContents* contents =
       browser()->tab_strip_model()->GetActiveWebContents();
   WaitForAccessibilityTreeToContainNodeWithName(contents,
                                                 "1 First Section\r\n");
 
   content::WebContents* guest_contents = nullptr;
@@ skipping 287 matching lines @@
   ASSERT_EQ(web_contents, active_web_contents);
 
   content::WebContents* new_web_contents =
       browser()->tab_strip_model()->GetWebContentsAt(1);
   ASSERT_TRUE(new_web_contents);
   ASSERT_NE(web_contents, new_web_contents);
 
   const GURL& url = new_web_contents->GetURL();
   ASSERT_EQ(GURL("http://www.example.com"), url);
 }