all: skip slow tests in short mode

Updates golang/go#14113
Updates golang/go#11811

Change-Id: I61851de12ff474d3b738fc88f402742677973cae

Author: bradfitz

go/loader/stdlib_test.go

@@ -32,6 +32,9 @@ func TestStdlib(t *testing.T) {
 	if runtime.GOOS == "android" {
 		t.Skipf("incomplete std lib on %s", runtime.GOOS)
 	}
+	if testing.Short() {
+		t.Skip("skipping in short mode; uses tons of memory (golang.org/issue/14113)")
+	}
 
 	runtime.GC()
 	t0 := time.Now()
@@ -118,6 +121,9 @@ func TestStdlib(t *testing.T) {
 }
 
 func TestCgoOption(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping in short mode; uses tons of memory (golang.org/issue/14113)")
+	}
 	switch runtime.GOOS {
 	// On these systems, the net and os/user packages don't use cgo
 	// or the std library is incomplete (Android).

go/pointer/pointer_test.go

@@ -522,6 +522,9 @@ func checkWarningExpectation(prog *ssa.Program, e *expectation, warnings []point
 }
 
 func TestInput(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping in short mode; this test requires tons of memory; golang.org/issue/14113")
+	}
 	ok := true
 
 	wd, err := os.Getwd()

go/ssa/stdlib_test.go

@@ -47,6 +47,9 @@ func bytesAllocated() uint64 {
 }
 
 func TestStdlib(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping in short mode; too slow (golang.org/issue/14113)")
+	}
 	// Load, parse and type-check the program.
 	t0 := time.Now()
 	alloc0 := bytesAllocated()