PrintPreview: Hide/Show the header footer option based on print frame margins.

chrome/renderer/print_web_view_helper.cc

Index: chrome/renderer/print_web_view_helper.cc
diff --git a/chrome/renderer/print_web_view_helper.cc b/chrome/renderer/print_web_view_helper.cc
index eca957e978ed6d57d038bee20f6e8a92118490fa..51d448743bed1e19295f2a541a57f5501b1125c3 100644
--- a/chrome/renderer/print_web_view_helper.cc
+++ b/chrome/renderer/print_web_view_helper.cc
@@ -852,7 +852,11 @@ void PrintWebViewHelper::OnPrintPreview(const DictionaryValue& settings) {
   }
   print_preview_context_.set_generate_draft_pages(generate_draft_pages);
 
-  if (CreatePreviewDocument()) {
+  int margins_type = 0;
+  if (!settings.GetInteger(printing::kSettingMarginsType, &margins_type))
+    margins_type = printing::DEFAULT_MARGINS;
+
+  if (CreatePreviewDocument(margins_type)) {
     DidFinishPrinting(OK);
   } else {
     if (notify_browser_of_print_failure_)
@@ -861,7 +865,7 @@ void PrintWebViewHelper::OnPrintPreview(const DictionaryValue& settings) {
   }
 }
 
-bool PrintWebViewHelper::CreatePreviewDocument() {
+bool PrintWebViewHelper::CreatePreviewDocument(int margins_type) {
   PrintMsg_Print_Params print_params = print_pages_params_->params;
   const std::vector<int>& pages = print_pages_params_->pages;
   if (!print_preview_context_.CreatePreviewDocument(&print_params, pages,
@@ -874,20 +878,47 @@ bool PrintWebViewHelper::CreatePreviewDocument() {
   ComputePageLayoutInPointsForCss(print_preview_context_.frame(), 0,
                                   print_params, ignore_css_margins_,
                                   fit_to_page_, NULL, &default_page_layout);
+
+  bool preview_is_modifiable = print_preview_context_.IsModifiable();
   if (!old_print_pages_params_.get() ||
       !PageLayoutIsEqual(*old_print_pages_params_, *print_pages_params_)) {
     bool has_page_size_style = PrintingFrameHasPageSizeStyle(
         print_preview_context_.frame(),
         print_preview_context_.total_page_count());
+
+    bool header_footer_applies = true;

[vandebo (ex-Chrome), 2012/03/15 21:47:17]

It seems like this is solely concerned with the presentation of the print
preview and therefore should live entirely in the javascript if possible.   From
our discussion, that means sending the printable are to javascript, which seems
reasonable.

[kmadhusu, 2012/03/17 00:29:12]

Done.

+    if (!preview_is_modifiable || margins_type == printing::NO_MARGINS) {
+      header_footer_applies = false;
+    } else if (margins_type != printing::PRINTABLE_AREA_MARGINS) {
+#if defined(OS_LINUX)
+    header_footer_applies =
+        (default_page_layout.margin_top > 0) ||
+        (default_page_layout.margin_bottom > 0);
+#else
+    int dpi = GetDPI(&print_params);
+    int non_printable_area_top = ConvertUnit(
+        print_pages_params_->params.printable_area.y(),
+            dpi, printing::kPointsPerInch);
+    int non_printable_area_bottom = ConvertUnit(
+        print_pages_params_->params.page_size.height() -
+            print_pages_params_->params.printable_area.y() -
+            print_pages_params_->params.printable_area.height(),
+        dpi, printing::kPointsPerInch);
+    header_footer_applies =
+        (default_page_layout.margin_top > non_printable_area_top) ||
+        (default_page_layout.margin_bottom > non_printable_area_bottom);
+#endif
+    }
     // Margins: Send default page layout to browser process.
     Send(new PrintHostMsg_DidGetDefaultPageLayout(routing_id(),
                                                   default_page_layout,
-                                                  has_page_size_style));
+                                                  has_page_size_style,
+                                                  header_footer_applies));
   }
 
   PrintHostMsg_DidGetPreviewPageCount_Params params;
   params.page_count = print_preview_context_.total_page_count();
-  params.is_modifiable = print_preview_context_.IsModifiable();
+  params.is_modifiable = preview_is_modifiable;
   params.document_cookie = print_pages_params_->params.document_cookie;
   params.preview_request_id = print_pages_params_->params.preview_request_id;
   params.clear_preview_data = print_preview_context_.generate_draft_pages();