OOP PDF: Fix PrintWebViewHelper test issues with OOP PDF enabled.

chrome/renderer/printing/print_web_view_helper.cc

Index: chrome/renderer/printing/print_web_view_helper.cc
diff --git a/chrome/renderer/printing/print_web_view_helper.cc b/chrome/renderer/printing/print_web_view_helper.cc
index 892505fe344c908c7475e28034ba4cc838712b21..da209a297117515a0d6408159d6e7735633f7d5f 100644
--- a/chrome/renderer/printing/print_web_view_helper.cc
+++ b/chrome/renderer/printing/print_web_view_helper.cc
@@ -904,14 +904,13 @@ void PrintWebViewHelper::OnPrintForPrintPreview(
     return;
   }
 
-  // The out-of-process plugin element is nested within a frame.
+  // The out-of-process plugin element is nested within a frame. In tests, there
+  // may not be an iframe containing the out-of-process plugin, so continue with
+  // the element with ID "pdf-viewer" if it isn't an iframe.
   blink::WebLocalFrame* plugin_frame = pdf_element.document().frame();
   blink::WebElement plugin_element = pdf_element;
-  if (switches::OutOfProcessPdfEnabled()) {
-    if (!pdf_element.hasHTMLTagName("iframe")) {
-      NOTREACHED();
-      return;
-    }
+  if (switches::OutOfProcessPdfEnabled() &&
+      pdf_element.hasHTMLTagName("iframe")) {
     plugin_frame = blink::WebLocalFrame::fromFrameOwnerElement(pdf_element);
     plugin_element = GetPdfElement(plugin_frame);
     if (plugin_element.isNull()) {