deps: update v8_inspector

Pick up latest commit of v8_inspector and inspector_protocol.
This brings back compatibility with V8 5.1.

PR-URL: #7385
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>

deps/v8_inspector/platform/v8_inspector/V8Compat.h

@@ -7,7 +7,7 @@
 
 #include <v8.h>
 
-#if V8_MAJOR_VERSION < 5 || (V8_MAJOR_VERSION == 5 && V8_MINOR_VERSION < 2)
+#if V8_MAJOR_VERSION < 5 || (V8_MAJOR_VERSION == 5 && V8_MINOR_VERSION < 1)
 namespace v8 {
 
 // In standalone V8 inspector this is expected to be noop anyways...