Sema: A couple of type checker tests were incorrectly in the 'slow' directory

They're actually fast.

Also, change -solver-expression-time-threshold=1 into a scope limit to make it
deterministic.

Author: slavapestov

validation-test/Sema/type_checker_perf/fast/issue-43715.swift

@@ -0,0 +1,5 @@
+// RUN: %target-typecheck-verify-swift -solver-scope-threshold=300
+
+func slow(someOptionalString: String?) {
+  print("\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")\(someOptionalString ?? "")")
+}

validation-test/Sema/type_checker_perf/fast/issue-43943.swift.gyb

@@ -0,0 +1,20 @@
+// RUN: %scale-test --begin 1 --end 6 --step 1 --select NumLeafScopes %s
+// REQUIRES: asserts,no_asan
+
+extension String {
+  func replacingOccurrences(of: String, with: String) -> String {
+    return ""
+  }
+}
+
+func slow(something: String?) {
+  var str = ""
+
+  [
+%for i in range(0, N):
+    ("${i}", something ?? ""),
+%end
+  ].forEach {
+    str = str.replacingOccurrences(of: $0, with: $1)
+  }
+}

validation-test/Sema/type_checker_perf/slow/rdar23327871.swift.gyb renamed to validation-test/Sema/type_checker_perf/fast/rdar23327871.swift.gyb

@@ -1,4 +1,4 @@
-// RUN: %scale-test --begin 8 --end 16 --step 1 --select NumLeafScopes %s -Xfrontend=-solver-expression-time-threshold=1
+// RUN: %scale-test --begin 8 --end 16 --step 1 --select NumLeafScopes %s
 // REQUIRES: asserts,no_asan
 
 let i = 1

validation-test/Sema/type_checker_perf/fast/rdar25866240.swift.gyb

@@ -0,0 +1,11 @@
+// RUN: not %scale-test --begin 1 --end 5 --step 1 --select incrementScopeCounter %s
+// REQUIRES: OS=macosx
+// REQUIRES: asserts
+
+func f() {
+% for i in range(N):
+  let collection${i} = [String]()
+% end
+
+  _ = ${' + '.join("collection%s" % i for i in range(N))}
+}

validation-test/Sema/type_checker_perf/fast/rdar33688063.swift

@@ -1,4 +1,4 @@
-// RUN: %target-typecheck-verify-swift -solver-expression-time-threshold=1
+// RUN: %target-typecheck-verify-swift -solver-scope-threshold=200
 // REQUIRES: tools-release,no_asan
 
 let _ = 1 | UInt32(0) << 0 | UInt32(1) << 1 | UInt32(2) << 2 | UInt32(3) << 3 | UInt32(4) << 4