Disable SwitchingAllTextInputTest

TextInput_TextInputStateChangedTest.SwitchingAllTextInputTest is flaky on Linux
Chromium OS Ozone bots. Disabling until it can be looked at by owners.

TBR=shuchen@chromium.org
BUG=458549

Review URL: https://codereview.chromium.org/923073002

Cr-Commit-Position: refs/heads/master@{#316224}

chrome/browser/chromeos/input_method/textinput_browsertest.cc

@@ -230,7 +230,7 @@ IN_PROC_BROWSER_TEST_F(TextInput_TextInputStateChangedTest,
 }
 
 IN_PROC_BROWSER_TEST_F(TextInput_TextInputStateChangedTest,
-                       SwitchingAllTextInputTest) {
+                       DISABLED_SwitchingAllTextInputTest) {
   TextInputTestHelper helper;
   EXPECT_EQ(ui::TEXT_INPUT_TYPE_NONE, helper.GetTextInputType());