DevTools: introduce --custom-devtools-frontend flag.

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 6d7a341356f00a8dc41166fe162794a465ba657c..9eb659ebc1d6642a41227432f100d46d611695b5 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -830,6 +830,11 @@ const char kQuicMaxPacketLength[] = "quic-max-packet-length";
 
 // Specifies the version of QUIC to use.
 const char kQuicVersion[] = "quic-version";
+
+// Specifies the absolute path to the devtools front-end folder. This
+// front-end will be used for the remote debugging session.
+const char kRemoteDebuggingFrontend[] = "remote-debugging-frontend";
+
 // Porvides a list of addresses to discover DevTools remote debugging targets.
 // The format is <host>:<port>,...,<host>:port.
 const char kRemoteDebuggingTargets[] = "remote-debugging-targets";