Move precompilation-related flags to flags list.

runtime/bin/main.cc

Index: runtime/bin/main.cc
diff --git a/runtime/bin/main.cc b/runtime/bin/main.cc
index 464248693688501638eaa5d9c2a8d0de69cc6c3e..bb21b9f3cee09c503911b63dff4409f99acf72f2 100644
--- a/runtime/bin/main.cc
+++ b/runtime/bin/main.cc
@@ -340,7 +340,10 @@ static bool ProcessGenPrecompiledSnapshotOption(
     precompiled_snapshot_directory = arg;
   }
   gen_precompiled_snapshot = true;
+#if !defined(DART_PRECOMPILED_RUNTIME)
+  // The precompiled runtime has FLAG_precompilation set as const.
   vm_options->AddArgument("--precompilation");
+#endif
   return true;
 }
 
@@ -355,7 +358,10 @@ static bool ProcessRunPrecompiledSnapshotOption(
     precompiled_snapshot_directory = &precompiled_snapshot_directory[1];
   }
   run_precompiled_snapshot = true;
+#if !defined(DART_PRECOMPILED_RUNTIME)
+  // The precompiled runtime has FLAG_precompilation set as const.
   vm_options->AddArgument("--precompilation");
+#endif
   return true;
 }
 
@@ -1556,11 +1562,14 @@ void main(int argc, char** argv) {
     Platform::Exit(kErrorExitCode);
   }
 
+#if !defined(PRODUCT)
+  // Constant true in PRODUCT mode.
   if (generate_script_snapshot ||
       generate_full_snapshot_after_run ||
       run_full_snapshot) {
     vm_options.AddArgument("--load_deferred_eagerly");
   }
+#endif
 
 #if defined(DART_PRECOMPILER) && !defined(DART_NO_SNAPSHOT)
   // Always set --precompilation with dart_noopt.