Add DPI option selection to Print Preview.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 98748adabb4a3883751f5c37167abb6f6462ab20..ee50b945044c2d1afd443506b3a541791d3cd4c5 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -8447,6 +8447,12 @@ Keep your key file in a safe place. You will need it to create new versions of y
         <message name="IDS_PRINT_PREVIEW_MEDIA_SIZE_LABEL" desc="Media size option label. Provides user the option to change the size of the printed page.">
           Paper size
         </message>
+        <message name="IDS_PRINT_PREVIEW_DPI_LABEL" desc="Print quality option label. Provides user the option to select one of the print quality options defined for the printer.">
+          Quality
+        </message>
+        <message name="IDS_PRINT_PREVIEW_DPI_ITEM_LABEL" desc="Print quality option value text.">
+          <ph name="DPI">$1<ex>300</ex></ph> dpi
+        </message>
         <message name="IDS_PRINT_PREVIEW_NATIVE_DIALOG" desc="Option offering the user to open the native print dialog, displayed when the PDF viewer is missing or when print preview fails.">
           Print using system dialog…
         </message>