add a flag to enable/disable download interception on android

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index eb7c6beec42c4ac93d0643f119efaf979f8f4d6a..d869e8d13ea318810701385a122491e3f34453a0 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1124,6 +1124,12 @@ const char kEnableTabSwitcherInDocumentMode[] =
 
 // Switch to an existing tab for a suggestion opened from the New Tab Page.
 const char kNtpSwitchToExistingTab[] = "ntp-switch-to-existing-tab";
+
+// Enables Android DownloadManager to intercept downloads.
+const char kEnableDownloadInterception[] = "enable-download-interception";
+
+// Disables Android DownloadManager to intercept downloads.
+const char kDisableDownloadInterception[] = "disable-download-interception";
 #endif  // defined(OS_ANDROID)
 
 #if defined(USE_ASH)