Set DPI before using GetPdfPaperSizeDeviceUnits

Not setting DPI causes a modal error dialog to be shown for
Android printing code.

Review URL: https://codereview.chromium.org/75273005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235825 0039d316-1c4b-4281-b951-d872f2087c98

printing/printing_context_android.cc

@@ -138,6 +138,7 @@ PrintingContext::Result PrintingContextAndroid::UseDefaultSettings() {
   DCHECK(!in_print_job_);
 
   ResetSettings();
+  settings_.set_dpi(kDefaultPdfDpi);
   gfx::Size physical_size = GetPdfPaperSizeDeviceUnits();
   SetSizes(&settings_, kDefaultPdfDpi, physical_size.width(),
            physical_size.height());