predictors: Move the configuration of speculative prefetch to field trials.

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 68ab97c31b9a48d9fce33c33c44ac2e7b4fe53ba..31e4389f24daab24826735a57344eef0a2a9d594 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -783,24 +783,6 @@ const char kSimulateOutdatedNoAU[]          = "simulate-outdated-no-au";
 // Simulates an update being available.
 const char kSimulateUpgrade[]               = "simulate-upgrade";
 
-// Speculative resource prefetching.
-const char kSpeculativeResourcePrefetching[] =
-    "speculative-resource-prefetching";
-
-// Speculative resource prefetching is disabled.
-const char kSpeculativeResourcePrefetchingDisabled[] = "disabled";
-
-// Speculative resource prefetching is enabled.
-const char kSpeculativeResourcePrefetchingEnabled[] = "enabled";
-
-// Speculative resource prefetching is enabled for external requests.
-const char kSpeculativeResourcePrefetchingEnabledExternal[] =
-    "enabled-external-only";
-
-// Speculative resource prefetching will only learn about resources that need to
-// be prefetched but will not prefetch them.
-const char kSpeculativeResourcePrefetchingLearning[] = "learning";
-
 // Causes SSL key material to be logged to the specified file for debugging
 // purposes. See
 // https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/Key_Log_Format