Adding a chrome flag to control the touch selection granularity strategy used by Blink.

content/public/common/content_switches.cc

Index: content/public/common/content_switches.cc
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index 8d9bd67c5f1b93840f832d01edac53669d8492ca..7913c2463b277ea162f7cec1f8bfb1bfc520b756 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -776,6 +776,10 @@ const char kTestingFixedHttpsPort[]         = "testing-fixed-https-port";
 // Type of the current test harness ("browser" or "ui").
 const char kTestType[]                      = "test-type";
 
+// Controls how text selection granularity changes when touch text selection
+// handles are dragged.
+const char kTouchTextSelectionStrategy[]    = "touch-selection-strategy";
+
 // Causes TRACE_EVENT flags to be recorded beginning with shutdown. Optionally,
 // can specify the specific trace categories to include (e.g.
 // --trace-shutdown=base,net) otherwise, all events are recorded.