Remove tls13-split-handshakes flag.

This is no longer needed.

Change-Id: Ie6dba524ecccd265f7f80a910b40c0fe1800356b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/46526
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index e555f46..a9b5c82 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -51,32 +51,31 @@
 )
 
 var (
-	useValgrind              = flag.Bool("valgrind", false, "If true, run code under valgrind")
-	useGDB                   = flag.Bool("gdb", false, "If true, run BoringSSL code under gdb")
-	useLLDB                  = flag.Bool("lldb", false, "If true, run BoringSSL code under lldb")
-	useRR                    = flag.Bool("rr-record", false, "If true, run BoringSSL code under `rr record`.")
-	waitForDebugger          = flag.Bool("wait-for-debugger", false, "If true, jobs will run one at a time and pause for a debugger to attach")
-	flagDebug                = flag.Bool("debug", false, "Hexdump the contents of the connection")
-	mallocTest               = flag.Int64("malloc-test", -1, "If non-negative, run each test with each malloc in turn failing from the given number onwards.")
-	mallocTestDebug          = flag.Bool("malloc-test-debug", false, "If true, ask bssl_shim to abort rather than fail a malloc. This can be used with a specific value for --malloc-test to identity the malloc failing that is causing problems.")
-	jsonOutput               = flag.String("json-output", "", "The file to output JSON results to.")
-	pipe                     = flag.Bool("pipe", false, "If true, print status output suitable for piping into another program.")
-	testToRun                = flag.String("test", "", "Semicolon-separated patterns of tests to run, or empty to run all tests")
-	skipTest                 = flag.String("skip", "", "Semicolon-separated patterns of tests to skip")
-	numWorkersFlag           = flag.Int("num-workers", runtime.NumCPU(), "The number of workers to run in parallel.")
-	shimPath                 = flag.String("shim-path", "../../../build/ssl/test/bssl_shim", "The location of the shim binary.")
-	handshakerPath           = flag.String("handshaker-path", "../../../build/ssl/test/handshaker", "The location of the handshaker binary.")
-	resourceDir              = flag.String("resource-dir", ".", "The directory in which to find certificate and key files.")
-	fuzzer                   = flag.Bool("fuzzer", false, "If true, tests against a BoringSSL built in fuzzer mode.")
-	transcriptDir            = flag.String("transcript-dir", "", "The directory in which to write transcripts.")
-	idleTimeout              = flag.Duration("idle-timeout", 15*time.Second, "The number of seconds to wait for a read or write to bssl_shim.")
-	deterministic            = flag.Bool("deterministic", false, "If true, uses a deterministic PRNG in the runner.")
-	allowUnimplemented       = flag.Bool("allow-unimplemented", false, "If true, report pass even if some tests are unimplemented.")
-	looseErrors              = flag.Bool("loose-errors", false, "If true, allow shims to report an untranslated error code.")
-	shimConfigFile           = flag.String("shim-config", "", "A config file to use to configure the tests for this shim.")
-	includeDisabled          = flag.Bool("include-disabled", false, "If true, also runs disabled tests.")
-	repeatUntilFailure       = flag.Bool("repeat-until-failure", false, "If true, the first selected test will be run repeatedly until failure.")
-	tls13SplitHandshakeTests = flag.Bool("tls13-split-handshake-tests", true, "If true, TLS 1.3 tests that use the handshaker will be performed")
+	useValgrind        = flag.Bool("valgrind", false, "If true, run code under valgrind")
+	useGDB             = flag.Bool("gdb", false, "If true, run BoringSSL code under gdb")
+	useLLDB            = flag.Bool("lldb", false, "If true, run BoringSSL code under lldb")
+	useRR              = flag.Bool("rr-record", false, "If true, run BoringSSL code under `rr record`.")
+	waitForDebugger    = flag.Bool("wait-for-debugger", false, "If true, jobs will run one at a time and pause for a debugger to attach")
+	flagDebug          = flag.Bool("debug", false, "Hexdump the contents of the connection")
+	mallocTest         = flag.Int64("malloc-test", -1, "If non-negative, run each test with each malloc in turn failing from the given number onwards.")
+	mallocTestDebug    = flag.Bool("malloc-test-debug", false, "If true, ask bssl_shim to abort rather than fail a malloc. This can be used with a specific value for --malloc-test to identity the malloc failing that is causing problems.")
+	jsonOutput         = flag.String("json-output", "", "The file to output JSON results to.")
+	pipe               = flag.Bool("pipe", false, "If true, print status output suitable for piping into another program.")
+	testToRun          = flag.String("test", "", "Semicolon-separated patterns of tests to run, or empty to run all tests")
+	skipTest           = flag.String("skip", "", "Semicolon-separated patterns of tests to skip")
+	numWorkersFlag     = flag.Int("num-workers", runtime.NumCPU(), "The number of workers to run in parallel.")
+	shimPath           = flag.String("shim-path", "../../../build/ssl/test/bssl_shim", "The location of the shim binary.")
+	handshakerPath     = flag.String("handshaker-path", "../../../build/ssl/test/handshaker", "The location of the handshaker binary.")
+	resourceDir        = flag.String("resource-dir", ".", "The directory in which to find certificate and key files.")
+	fuzzer             = flag.Bool("fuzzer", false, "If true, tests against a BoringSSL built in fuzzer mode.")
+	transcriptDir      = flag.String("transcript-dir", "", "The directory in which to write transcripts.")
+	idleTimeout        = flag.Duration("idle-timeout", 15*time.Second, "The number of seconds to wait for a read or write to bssl_shim.")
+	deterministic      = flag.Bool("deterministic", false, "If true, uses a deterministic PRNG in the runner.")
+	allowUnimplemented = flag.Bool("allow-unimplemented", false, "If true, report pass even if some tests are unimplemented.")
+	looseErrors        = flag.Bool("loose-errors", false, "If true, allow shims to report an untranslated error code.")
+	shimConfigFile     = flag.String("shim-config", "", "A config file to use to configure the tests for this shim.")
+	includeDisabled    = flag.Bool("include-disabled", false, "If true, also runs disabled tests.")
+	repeatUntilFailure = flag.Bool("repeat-until-failure", false, "If true, the first selected test will be run repeatedly until failure.")
 )
 
 // ShimConfigurations is used with the “json” package and represents a shim
@@ -1835,16 +1834,6 @@
 			strings.HasPrefix(test.name, "VersionNegotiation-") {
 			continue
 		}
-		// TODO(mab): Remove this when it's no longer needed.
-		//
-		// This flag exists to allow TLS 1.3 support to propagate to old
-		// versions, before enabling cross-version compatibility tests.
-		if !*tls13SplitHandshakeTests &&
-			(test.config.MaxVersion >= VersionTLS13 ||
-				test.config.MaxVersion < VersionTLS10 ||
-				(test.resumeConfig != nil && (test.resumeConfig.MaxVersion < VersionTLS10 || test.resumeConfig.MaxVersion >= VersionTLS13))) {
-			continue
-		}
 
 		for _, flag := range test.flags {
 			if flag == "-implicit-handshake" {