diff --git a/atom/browser/atom_resource_dispatcher_host_delegate.cc b/atom/browser/atom_resource_dispatcher_host_delegate.cc
index 7ee1df4a8d..aa65203caf 100644
--- a/atom/browser/atom_resource_dispatcher_host_delegate.cc
+++ b/atom/browser/atom_resource_dispatcher_host_delegate.cc
@@ -7,8 +7,8 @@
 #include "atom/browser/atom_browser_context.h"
 #include "atom/browser/login_handler.h"
 #include "atom/browser/stream_manager.h"
-#include "atom/browser/ui/webui/pdf_viewer_ui.h"
 #include "atom/browser/web_contents_permission_helper.h"
+#include "atom/common/atom_constants.h"
 #include "atom/common/platform_util.h"
 #include "base/guid.h"
 #include "base/strings/stringprintf.h"
@@ -81,8 +81,8 @@ void OnPdfStreamCreated(
   stream_manager->AddStream(std::move(stream), view_id, render_process_id,
                             render_frame_id);
   content::NavigationController::LoadURLParams params(GURL(base::StringPrintf(
-      "%sindex.html?%s=%s&%s=%s", PdfViewerUI::kOrigin, PdfViewerUI::kId,
-      view_id.c_str(), PdfViewerUI::kSrc, original_url.spec().c_str())));
+      "%sindex.html?%s=%s&%s=%s", kPdfViewerUIOrigin, kPdfViewerUIId,
+      view_id.c_str(), kPdfPluginSrc, original_url.spec().c_str())));
   web_contents->GetController().LoadURLWithParams(params);
 }
 
@@ -131,7 +131,7 @@ bool AtomResourceDispatcherHostDelegate::ShouldInterceptResourceAsStream(
     GURL* origin,
     std::string* payload) {
   if (mime_type == "application/pdf") {
-    *origin = GURL(PdfViewerUI::kOrigin);
+    *origin = GURL(kPdfViewerUIOrigin);
     return true;
   }
   return false;
diff --git a/atom/browser/atom_web_ui_controller_factory.cc b/atom/browser/atom_web_ui_controller_factory.cc
index b945ae02f2..0172a3c4c7 100644
--- a/atom/browser/atom_web_ui_controller_factory.cc
+++ b/atom/browser/atom_web_ui_controller_factory.cc
@@ -7,6 +7,7 @@
 #include <string>
 
 #include "atom/browser/ui/webui/pdf_viewer_ui.h"
+#include "atom/common/atom_constants.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "content/public/browser/web_contents.h"
@@ -25,7 +26,7 @@ AtomWebUIControllerFactory::~AtomWebUIControllerFactory() {}
 content::WebUI::TypeID AtomWebUIControllerFactory::GetWebUIType(
     content::BrowserContext* browser_context,
     const GURL& url) const {
-  if (url.host() == PdfViewerUI::kHost) {
+  if (url.host() == kPdfViewerUIHost) {
     return const_cast<AtomWebUIControllerFactory*>(this);
   }
 
@@ -47,14 +48,14 @@ bool AtomWebUIControllerFactory::UseWebUIBindingsForURL(
 content::WebUIController*
 AtomWebUIControllerFactory::CreateWebUIControllerForURL(content::WebUI* web_ui,
                                                         const GURL& url) const {
-  if (url.host() == PdfViewerUI::kHost) {
+  if (url.host() == kPdfViewerUIHost) {
     base::StringPairs toplevel_params;
     base::SplitStringIntoKeyValuePairs(url.query(), '=', '&', &toplevel_params);
     std::string view_id, src;
     for (const auto& param : toplevel_params) {
-      if (param.first == PdfViewerUI::kId) {
+      if (param.first == kPdfViewerUIId) {
         view_id = param.second;
-      } else if (param.first == PdfViewerUI::kSrc) {
+      } else if (param.first == kPdfPluginSrc) {
         src = param.second;
       }
     }
diff --git a/atom/browser/ui/webui/pdf_viewer_handler.cc b/atom/browser/ui/webui/pdf_viewer_handler.cc
index 37b18de39e..6c86173043 100644
--- a/atom/browser/ui/webui/pdf_viewer_handler.cc
+++ b/atom/browser/ui/webui/pdf_viewer_handler.cc
@@ -4,6 +4,7 @@
 
 #include "atom/browser/ui/webui/pdf_viewer_handler.h"
 
+#include "atom/common/atom_constants.h"
 #include "base/bind.h"
 #include "base/values.h"
 #include "content/public/browser/stream_handle.h"
@@ -11,6 +12,7 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/common/page_zoom.h"
+#include "content/public/common/url_constants.h"
 #include "net/http/http_response_headers.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/webui/web_ui_util.h"
@@ -145,7 +147,6 @@ void PdfViewerHandler::GetStrings(const base::ListValue* args) {
   SET_STRING("labelPageNumber", "Page number");
   SET_STRING("tooltipRotateCW", "Rotate clockwise");
   SET_STRING("tooltipDownload", "Download");
-  SET_STRING("tooltipPrint", "Print");
   SET_STRING("tooltipFitToPage", "Fit to page");
   SET_STRING("tooltipFitToWidth", "Fit to width");
   SET_STRING("tooltipZoomIn", "Zoom in");
@@ -161,7 +162,8 @@ void PdfViewerHandler::OnZoomLevelChanged(
     const content::HostZoomMap::ZoomLevelChange& change) {
   // TODO(deepak1556): This will work only if zoom level is changed through host
   // zoom map.
-  if (change.scheme == "chrome" && change.host == "pdf-viewer") {
+  if (change.scheme == content::kChromeUIScheme &&
+      change.host == kPdfViewerUIHost) {
     CallJavascriptFunction(
         "cr.webUIListenerCallback", base::StringValue("onZoomLevelChanged"),
         base::FundamentalValue(
diff --git a/atom/browser/ui/webui/pdf_viewer_ui.cc b/atom/browser/ui/webui/pdf_viewer_ui.cc
index 0c642a28ee..029a8e6dfb 100644
--- a/atom/browser/ui/webui/pdf_viewer_ui.cc
+++ b/atom/browser/ui/webui/pdf_viewer_ui.cc
@@ -9,6 +9,7 @@
 #include "atom/browser/atom_browser_context.h"
 #include "atom/browser/stream_manager.h"
 #include "atom/browser/ui/webui/pdf_viewer_handler.h"
+#include "atom/common/atom_constants.h"
 #include "components/pdf/common/pdf_messages.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/url_data_source.h"
@@ -23,7 +24,7 @@ namespace atom {
 namespace {
 
 std::string PathWithoutParams(const std::string& path) {
-  return GURL(PdfViewerUI::kOrigin + path).path().substr(1);
+  return GURL(kPdfViewerUIOrigin + path).path().substr(1);
 }
 
 class BundledDataSource : public content::URLDataSource {
@@ -41,7 +42,7 @@ class BundledDataSource : public content::URLDataSource {
   }
 
   // content::URLDataSource implementation.
-  std::string GetSource() const override { return PdfViewerUI::kHost; }
+  std::string GetSource() const override { return kPdfViewerUIHost; }
 
   void StartDataRequest(const std::string& path,
                         int render_process_id,
@@ -83,11 +84,6 @@ class BundledDataSource : public content::URLDataSource {
 
 }  // namespace
 
-const char PdfViewerUI::kOrigin[] = "chrome://pdf-viewer/";
-const char PdfViewerUI::kHost[] = "pdf-viewer";
-const char PdfViewerUI::kId[] = "viewId";
-const char PdfViewerUI::kSrc[] = "src";
-
 PdfViewerUI::PdfViewerUI(content::BrowserContext* browser_context,
                          content::WebUI* web_ui,
                          const std::string& view_id,
diff --git a/atom/browser/ui/webui/pdf_viewer_ui.h b/atom/browser/ui/webui/pdf_viewer_ui.h
index d81e12d69b..02a1f01af5 100644
--- a/atom/browser/ui/webui/pdf_viewer_ui.h
+++ b/atom/browser/ui/webui/pdf_viewer_ui.h
@@ -22,11 +22,6 @@ namespace atom {
 class PdfViewerUI : public content::WebUIController,
                     public content::WebContentsObserver {
  public:
-  static const char kOrigin[];
-  static const char kHost[];
-  static const char kId[];
-  static const char kSrc[];
-
   PdfViewerUI(content::BrowserContext* browser_context,
               content::WebUI* web_ui,
               const std::string& view_id,
diff --git a/atom/common/atom_constants.cc b/atom/common/atom_constants.cc
index e8a7c2f7aa..42f0d0031a 100644
--- a/atom/common/atom_constants.cc
+++ b/atom/common/atom_constants.cc
@@ -26,5 +26,10 @@ const char kSecureProtocolDescription[] =
 
 const char kPdfPluginMimeType[] = "application/x-google-chrome-pdf";
 const char kPdfPluginPath[] = "chrome://pdf-viewer/";
+const char kPdfPluginSrc[] = "src";
+
+const char kPdfViewerUIOrigin[] = "chrome://pdf-viewer/";
+const char kPdfViewerUIHost[] = "pdf-viewer";
+const char kPdfViewerUIId[] = "viewId";
 
 }  // namespace atom
diff --git a/atom/common/atom_constants.h b/atom/common/atom_constants.h
index 24186cf92c..ddd27d87ac 100644
--- a/atom/common/atom_constants.h
+++ b/atom/common/atom_constants.h
@@ -23,6 +23,12 @@ extern const char kSecureProtocolDescription[];
 // The MIME type used for the PDF plugin.
 extern const char kPdfPluginMimeType[];
 extern const char kPdfPluginPath[];
+extern const char kPdfPluginSrc[];
+
+// Constants for PDF viewer webui.
+extern const char kPdfViewerUIOrigin[];
+extern const char kPdfViewerUIHost[];
+extern const char kPdfViewerUIId[];
 
 }  // namespace atom