Mark printing code as basic printing and/or print preview code.

chrome/browser/ui/webui/print_preview/print_preview_handler.cc

 // Copyright (c) 2012 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/browser/ui/webui/print_preview/print_preview_handler.h"
 
 #include <ctype.h>
 #include <stddef.h>
 #include <map>
 #include <string>
@@ skipping 273 matching lines @@
   if (settings.GetBoolean(printing::kSettingOpenPDFInPreview,
                           &external_preview) && external_preview) {
     ReportPrintSettingHistogram(EXTERNAL_PDF_PREVIEW);
   }
 
   bool distill_page = false;
   if (settings.GetBoolean(printing::kSettingDistillPageEnabled,
                           &distill_page) && distill_page) {
     ReportPrintSettingHistogram(DISTILL_PAGE);
   }
-
 }
 
 // Callback that stores a PDF file on disk.
 void PrintToPdfCallback(const scoped_refptr<base::RefCountedBytes>& data,
                         const base::FilePath& path,
                         const base::Closure& pdf_file_saved_closure) {
   DCHECK_CURRENTLY_ON(BrowserThread::FILE);
   printing::PdfMetafileSkia metafile;
   metafile.InitFromData(static_cast<const void*>(data->front()), data->size());
   base::File file(path,
@@ skipping 692 matching lines @@
     // Nothing to print, no preview available.
     return;
   }
 
   if (is_cloud_printer) {
     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.PrintToCloudPrint",
                          page_count);
     ReportUserActionHistogram(PRINT_WITH_CLOUD_PRINT);
     SendCloudPrintJob(data.get());
   } else {
+#if defined(ENABLE_BASIC_PRINTING)

[Vitaly Buka (NO REVIEWS), 2016/01/04 21:36:49]

As I remember basic printing is system dialog printing.
I made some efforts to enable (enable_basic_printing==0 and
enable_print_preview==1) builds.

Idea was to remove system dialog at all. 
But having that mobile platforms use that code, it's not going to happen.

So are you removing (enable_basic_printing==0 and enable_print_preview==1) case
intentionally?

[Lei Zhang, 2016/01/07 03:01:09]

We have:
no printing - embedded platforms?
enable_basic_printing only - Android
enable_print_preview only - ChromeOS
full printing - desktop

I'm getting rid of the defined(OS_CHROME) checks in this CL. In particular:

PrintWebViewHelper::PrintPagesNative() has a ChromeOS NOTREACHED(), and if you
follow the call stack for that, we should never get here on ChromeOS either.
ChromeOS should always have |is_cloud_printer| set to true. But rather than
marking this block as !OS_CHROME, I'm using the ENABLE_BASIC_PRINTING feature
flag.

[Vitaly Buka (NO REVIEWS), 2016/01/07 04:19:35]

It was possible to build on Windows (don't remember, but maybe on other desktops
too) with ENABLE_BASIC_PRINTING and with no PRINT_PREVIEW, using gyp defines.

This is not enabled on any build bots, so that config is probably degraded.
There was attempt to get closer to removing ENABLE_BASIC_PRINTING from desktops
at all and keep print preview only.

[Vitaly Buka (NO REVIEWS), 2016/01/07 04:21:14]

Sorry, I tried to say:
it was possible to build "without ENABLE_BASIC_PRINTING and with PRINT_PREVIEW"

[Lei Zhang, 2016/01/07 04:47:50]

With this CL, all the configurations are buildable except for "no printing".
There's no bots to test, and I'm fine with that. I just want to have better
separation, so if we shuffle the code around in the future, it's easier to
identify what goes where.

[Vitaly Buka (NO REVIEWS), 2016/01/07 23:50:23]

Then I am fine with that too :-)

     bool system_dialog = false;
     settings->GetBoolean(printing::kSettingShowSystemDialog, &system_dialog);
     if (system_dialog) {
       UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.SystemDialog", page_count);
       ReportUserActionHistogram(FALLBACK_TO_ADVANCED_SETTINGS_DIALOG);
     } else {
       UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.PrintToPrinter", page_count);
       ReportUserActionHistogram(PRINT_TO_PRINTER);
     }
 
@@ skipping 30 matching lines @@
 
     // For all other cases above, the preview dialog will stay open until the
     // printing has finished. Then the dialog closes and PrintPreviewDone() gets
     // called. In the case below, since the preview dialog will be hidden and
     // not closed, we need to make this call.
     if (initiator) {
       printing::PrintViewManager* print_view_manager =
           printing::PrintViewManager::FromWebContents(initiator);
       print_view_manager->PrintPreviewDone();
     }
+#else
+    NOTREACHED();
+#endif   // defined(ENABLE_BASIC_PRINTING)
   }
 }
 
 void PrintPreviewHandler::PrintToPdf() {
   if (!print_to_pdf_path_.empty()) {
     // User has already selected a path, no need to show the dialog again.
     PostPrintToPdfTask();
   } else if (!select_file_dialog_.get() ||
              !select_file_dialog_->IsRunning(platform_util::GetTopLevel(
                  preview_web_contents()->GetNativeView()))) {
@@ skipping 753 matching lines @@
 
 void PrintPreviewHandler::UnregisterForGaiaCookieChanges() {
   if (gaia_cookie_manager_service_)
     gaia_cookie_manager_service_->RemoveObserver(this);
 }
 
 void PrintPreviewHandler::SetPdfSavedClosureForTesting(
     const base::Closure& closure) {
   pdf_file_saved_closure_ = closure;
 }