Revert "Remove cold mode idle time spellchecker flag"

This reverts commit d1c99618.

Reason for revert: Observed many crashes in M68 & M69. Not ready
for shipping.

Original change's description:
> Remove cold mode idle time spellchecker flag
>
> As cold mode idle time spellchecker is shipped into M68
> and no regression is obversed, this patch removes the flag
> from M69 as cleanup.
>
> Bug: 716642
> Change-Id: I8f850c52469590ee9d5e542c14f4dae842a6163a
> Reviewed-on: https://chromium-review.googlesource.com/1072953
> Reviewed-by: Kent Tamura <tkent@chromium.org>
> Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
> Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#561951}

TBR=yosin@chromium.org,tkent@chromium.org,xiaochengh@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 716642, 856376, 859056, 859443
Change-Id: I91426509a315a07bf4f548ebafe825c2ef856999
Reviewed-on: https://chromium-review.googlesource.com/1123120
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572086}

third_party/blink/renderer/core/editing/spellcheck/idle_spell_check_callback.cc

@@ -107,7 +107,8 @@ void IdleSpellCheckCallback::SetNeedsInvocation() {
 }
 
 void IdleSpellCheckCallback::SetNeedsColdModeInvocation() {
-  if (!IsSpellCheckingEnabled()) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled() ||
+      !IsSpellCheckingEnabled()) {
     Deactivate();
     return;
   }
@@ -125,6 +126,7 @@ void IdleSpellCheckCallback::SetNeedsColdModeInvocation() {
 }
 
 void IdleSpellCheckCallback::ColdModeTimerFired(TimerBase*) {
+  DCHECK(RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled());
   DCHECK_EQ(State::kColdModeTimerStarted, state_);
 
   if (!IsSpellCheckingEnabled() || !IsAvailable()) {
@@ -180,6 +182,7 @@ void IdleSpellCheckCallback::invoke(IdleDeadline* deadline) {
     HotModeInvocation(deadline);
     SetNeedsColdModeInvocation();
   } else if (state_ == State::kColdModeRequested) {
+    DCHECK(RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled());
     state_ = State::kInColdModeInvocation;
     cold_mode_requester_->Invoke(deadline);
     if (cold_mode_requester_->FullyChecked())

third_party/blink/renderer/core/editing/spellcheck/idle_spell_check_callback_test.cc

@@ -37,8 +37,10 @@ class IdleSpellCheckCallbackTest : public SpellCheckTestBase {
         IdleChecker().SetNeedsInvocation();
         break;
       case State::kColdModeTimerStarted:
+        DCHECK(RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled());
         break;
       case State::kColdModeRequested:
+        DCHECK(RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled());
         IdleChecker().SkipColdModeTimerForTesting();
         break;
       case State::kInHotModeInvocation:
@@ -51,9 +53,19 @@ class IdleSpellCheckCallbackTest : public SpellCheckTestBase {
 // Test cases for lifecycle state transitions.
 
 TEST_F(IdleSpellCheckCallbackTest, InitializationWithColdMode) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   EXPECT_EQ(State::kColdModeTimerStarted, IdleChecker().GetState());
 }
 
+TEST_F(IdleSpellCheckCallbackTest, InitializationWithoutColdMode) {
+  if (RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
+  EXPECT_EQ(State::kInactive, IdleChecker().GetState());
+}
+
 TEST_F(IdleSpellCheckCallbackTest, RequestWhenInactive) {
   TransitTo(State::kInactive);
   IdleChecker().SetNeedsInvocation();
@@ -71,6 +83,9 @@ TEST_F(IdleSpellCheckCallbackTest, RequestWhenHotModeRequested) {
 }
 
 TEST_F(IdleSpellCheckCallbackTest, RequestWhenColdModeTimerStarted) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeTimerStarted);
   IdleChecker().SetNeedsInvocation();
   EXPECT_EQ(State::kHotModeRequested, IdleChecker().GetState());
@@ -78,6 +93,9 @@ TEST_F(IdleSpellCheckCallbackTest, RequestWhenColdModeTimerStarted) {
 }
 
 TEST_F(IdleSpellCheckCallbackTest, RequestWhenColdModeRequested) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeRequested);
   int handle = IdleChecker().IdleCallbackHandle();
   IdleChecker().SetNeedsInvocation();
@@ -86,13 +104,28 @@ TEST_F(IdleSpellCheckCallbackTest, RequestWhenColdModeRequested) {
   EXPECT_NE(-1, IdleChecker().IdleCallbackHandle());
 }
 
+TEST_F(IdleSpellCheckCallbackTest, HotModeTransitToInactive) {
+  if (RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
+  TransitTo(State::kHotModeRequested);
+  IdleChecker().ForceInvocationForTesting();
+  EXPECT_EQ(State::kInactive, IdleChecker().GetState());
+}
+
 TEST_F(IdleSpellCheckCallbackTest, HotModeTransitToColdMode) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kHotModeRequested);
   IdleChecker().ForceInvocationForTesting();
   EXPECT_EQ(State::kColdModeTimerStarted, IdleChecker().GetState());
 }
 
 TEST_F(IdleSpellCheckCallbackTest, ColdModeTimerStartedToRequested) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeTimerStarted);
   IdleChecker().SkipColdModeTimerForTesting();
   EXPECT_EQ(State::kColdModeRequested, IdleChecker().GetState());
@@ -100,6 +133,9 @@ TEST_F(IdleSpellCheckCallbackTest, ColdModeTimerStartedToRequested) {
 }
 
 TEST_F(IdleSpellCheckCallbackTest, ColdModeStayAtColdMode) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeRequested);
   IdleChecker().SetNeedsMoreColdModeInvocationForTesting();
   IdleChecker().ForceInvocationForTesting();
@@ -107,6 +143,9 @@ TEST_F(IdleSpellCheckCallbackTest, ColdModeStayAtColdMode) {
 }
 
 TEST_F(IdleSpellCheckCallbackTest, ColdModeToInactive) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeRequested);
   IdleChecker().ForceInvocationForTesting();
   EXPECT_EQ(State::kInactive, IdleChecker().GetState());
@@ -125,12 +164,18 @@ TEST_F(IdleSpellCheckCallbackTest, DetachWhenHotModeRequested) {
 }
 
 TEST_F(IdleSpellCheckCallbackTest, DetachWhenColdModeTimerStarted) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeTimerStarted);
   GetDocument().Shutdown();
   EXPECT_EQ(State::kInactive, IdleChecker().GetState());
 }
 
 TEST_F(IdleSpellCheckCallbackTest, DetachWhenColdModeRequested) {
+  if (!RuntimeEnabledFeatures::IdleTimeColdModeSpellCheckingEnabled())
+    return;
+
   TransitTo(State::kColdModeRequested);
   GetDocument().Shutdown();
   EXPECT_EQ(State::kInactive, IdleChecker().GetState());

third_party/blink/renderer/platform/runtime_enabled_features.json5

@@ -572,6 +572,10 @@
       name: "IDBObserver",
       status: "experimental",
     },
+    {
+      name: "IdleTimeColdModeSpellChecking",
+      status: "stable",
+    },
     {
       name: "ImageDecodingAttribute",
       status: "stable",