copying to clipboard should add a newline before the content of the next page.

pdf/pdfium/pdfium_engine.cc

Index: pdf/pdfium/pdfium_engine.cc
diff --git a/pdf/pdfium/pdfium_engine.cc b/pdf/pdfium/pdfium_engine.cc
index 6cd9cae4f9974104ef0879c11b3732ba52a23964..5920af1ee5c5427ca6e5001b30b7ad7a38e560b4 100644
--- a/pdf/pdfium/pdfium_engine.cc
+++ b/pdf/pdfium/pdfium_engine.cc
@@ -2229,11 +2229,14 @@ void PDFiumEngine::InvalidateAllPages() {
 
 std::string PDFiumEngine::GetSelectedText() {
   base::string16 result;
+  base::string16 new_line_char = base::UTF8ToUTF16("\n");
   for (size_t i = 0; i < selection_.size(); ++i) {
     if (i > 0 &&
         selection_[i - 1].page_index() > selection_[i].page_index()) {
-      result = selection_[i].GetText() + result;
+      result = selection_[i].GetText() + new_line_char + result;
     } else {
+      if (i > 0)
+        result.append(new_line_char);
       result.append(selection_[i].GetText());
     }
   }