Add superficial unit test for PrintJob. That's a start....

chrome/renderer/render_view.cc

 // Copyright (c) 2006-2008 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 "chrome/renderer/render_view.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 435 matching lines @@
   // Safari uses: 765 & 1224. Margins aren't exactly the same either.
   // Scale = 2.222 for MDI printer.
   int pages;
   if (!frame->SetPrintingMode(true,
                               minLayoutWidth,
                               maxLayoutWidth,
                               &printed_document_width_)) {
     NOTREACHED();
     pages = 0;
   } else {
+    DCHECK_GT(printed_document_width_, 0);
     // Force to recalculate the height, otherwise it reuse the current window
     // height as the default.
     float effective_shrink = printed_document_width_ / paper_width;
     gfx::Size page_size(printed_document_width_,
                         static_cast<int>(paper_height * effective_shrink) - 1);
     WebView* view = frame->GetView();
     if (view) {
       // Hack around an issue where if the current view height is higher than
       // the page height, empty pages will be printed even if the bottom of the
       // web page is empty.
@@ skipping 2260 matching lines @@
           template_resource_id));
 
   if (template_html.empty()) {
     NOTREACHED() << "unable to load template. ID: " << template_resource_id;
     return "";
   }
   // "t" is the id of the templates root node.
   return jstemplate_builder::GetTemplateHtml(
       template_html, &error_strings, "t");
 }