[turbofan] Remove obsolete --turbo-try-catch flag.

test/cctest/compiler/test-run-deopt.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/frames-inl.h"
 #include "test/cctest/cctest.h"
 #include "test/cctest/compiler/function-tester.h"
 
@@ skipping 45 matching lines @@
       "  return d + a;"
       "})");
 
   InstallIsOptimizedHelper(CcTest::isolate());
   T.CheckCall(T.Val(6), T.Val(3));
 }
 
 
 TEST(DeoptExceptionHandlerCatch) {
   FLAG_allow_natives_syntax = true;
-  FLAG_turbo_try_catch = true;
 
   FunctionTester T(
       "(function f() {"
       "  var is_opt = IsOptimized;"
       "  try {"
       "    DeoptAndThrow(f);"
       "  } catch (e) {"
       "    return is_opt();"
       "  }"
       "})");
@@ skipping 30 matching lines @@
   FLAG_allow_natives_syntax = true;
 
   FunctionTester T(
       "(function foo() {"
       "  %DeoptimizeFunction(foo);"
       "  return 1;"
       "})");
 
   T.CheckCall(T.Val(1));
 }