Removed --disable-print-preview switch and policy.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 8847ae3f2edc65142f1524febc5aa449d28d3735..b6a708d7d72531b633d5a40cec751f03510fd019 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -1168,9 +1168,6 @@ const char kInvertNotificationShown[] = "invert_notification_version_2_shown";
 // Boolean controlling whether printing is enabled.
 const char kPrintingEnabled[] = "printing.enabled";
 
-// Boolean controlling whether print preview is disabled.
-const char kPrintPreviewDisabled[] = "printing.print_preview_disabled";
-
 // An integer pref specifying the fallback behavior for sites outside of content
 // packs. One of:
 // 0: Allow (does nothing)