Revert of Streams: Remove isTerminating() calls

third_party/WebKit/Source/core/streams/ReadableStreamOperations.cpp

Index: third_party/WebKit/Source/core/streams/ReadableStreamOperations.cpp
diff --git a/third_party/WebKit/Source/core/streams/ReadableStreamOperations.cpp b/third_party/WebKit/Source/core/streams/ReadableStreamOperations.cpp
index a3408ddcf05115d6280d9d1b766ae6b8f83956c1..3cc883fa8c2311d6607183005ded319e7b8ac988 100644
--- a/third_party/WebKit/Source/core/streams/ReadableStreamOperations.cpp
+++ b/third_party/WebKit/Source/core/streams/ReadableStreamOperations.cpp
@@ -8,32 +8,59 @@
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/ToV8.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
+#include "bindings/core/v8/WorkerOrWorkletScriptController.h"
 #include "core/streams/UnderlyingSourceBase.h"
+#include "core/workers/WorkerGlobalScope.h"
 
 namespace blink {
 
+namespace {
+
+bool isTerminating(ScriptState* scriptState)
+{
+    ExecutionContext* executionContext = scriptState->getExecutionContext();
+    if (!executionContext)
+        return true;
+    if (!executionContext->isWorkerGlobalScope())
+        return false;
+    return toWorkerGlobalScope(executionContext)->scriptController()->isExecutionTerminating();
+}
+
+} // namespace
+
 ScriptValue ReadableStreamOperations::createReadableStream(ScriptState* scriptState, UnderlyingSourceBase* underlyingSource, ScriptValue strategy)
 {
+    if (isTerminating(scriptState))
+        return ScriptValue();
     ScriptState::Scope scope(scriptState);
 
     v8::Local<v8::Value> jsUnderlyingSource = toV8(underlyingSource, scriptState);
     v8::Local<v8::Value> jsStrategy = strategy.v8Value();
     v8::Local<v8::Value> args[] = { jsUnderlyingSource, jsStrategy };
     v8::MaybeLocal<v8::Value> jsStream = V8ScriptRunner::callExtra(scriptState, "createReadableStreamWithExternalController", args);
+    if (isTerminating(scriptState))
+        return ScriptValue();
     return ScriptValue(scriptState, jsStream.ToLocalChecked());
 }
 
 ScriptValue ReadableStreamOperations::createCountQueuingStrategy(ScriptState* scriptState, size_t highWaterMark)
 {
+    if (isTerminating(scriptState))
+        return ScriptValue();
     ScriptState::Scope scope(scriptState);
 
     v8::Local<v8::Value> args[] = { v8::Number::New(scriptState->isolate(), highWaterMark) };
     v8::MaybeLocal<v8::Value> jsStrategy = V8ScriptRunner::callExtra(scriptState, "createBuiltInCountQueuingStrategy", args);
+    if (isTerminating(scriptState))
+        return ScriptValue();
+
     return ScriptValue(scriptState, jsStrategy.ToLocalChecked());
 }
 
 ScriptValue ReadableStreamOperations::getReader(ScriptState* scriptState, ScriptValue stream, ExceptionState& es)
 {
+    if (isTerminating(scriptState))
+        return ScriptValue();
     ASSERT(isReadableStream(scriptState, stream));
 
     v8::TryCatch block(scriptState->isolate());
@@ -46,6 +73,8 @@
 
 bool ReadableStreamOperations::isReadableStream(ScriptState* scriptState, ScriptValue value)
 {
+    if (isTerminating(scriptState))
+        return true;
     ASSERT(!value.isEmpty());
 
     if (!value.isObject())
@@ -53,56 +82,80 @@
 
     v8::Local<v8::Value> args[] = { value.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "IsReadableStream", args);
+    if (isTerminating(scriptState))
+        return true;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 bool ReadableStreamOperations::isDisturbed(ScriptState* scriptState, ScriptValue stream)
 {
+    if (isTerminating(scriptState))
+        return true;
     ASSERT(isReadableStream(scriptState, stream));
 
     v8::Local<v8::Value> args[] = { stream.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "IsReadableStreamDisturbed", args);
+    if (isTerminating(scriptState))
+        return true;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 bool ReadableStreamOperations::isLocked(ScriptState* scriptState, ScriptValue stream)
 {
+    if (isTerminating(scriptState))
+        return true;
     ASSERT(isReadableStream(scriptState, stream));
 
     v8::Local<v8::Value> args[] = { stream.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "IsReadableStreamLocked", args);
+    if (isTerminating(scriptState))
+        return true;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 bool ReadableStreamOperations::isReadable(ScriptState* scriptState, ScriptValue stream)
 {
+    if (isTerminating(scriptState))
+        return false;
     ASSERT(isReadableStream(scriptState, stream));
 
     v8::Local<v8::Value> args[] = { stream.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtraOrCrash(scriptState, "IsReadableStreamReadable", args);
+    if (isTerminating(scriptState))
+        return false;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 bool ReadableStreamOperations::isClosed(ScriptState* scriptState, ScriptValue stream)
 {
+    if (isTerminating(scriptState))
+        return false;
     ASSERT(isReadableStream(scriptState, stream));
 
     v8::Local<v8::Value> args[] = { stream.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "IsReadableStreamClosed", args);
+    if (isTerminating(scriptState))
+        return false;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 bool ReadableStreamOperations::isErrored(ScriptState* scriptState, ScriptValue stream)
 {
+    if (isTerminating(scriptState))
+        return true;
     ASSERT(isReadableStream(scriptState, stream));
 
     v8::Local<v8::Value> args[] = { stream.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "IsReadableStreamErrored", args);
+    if (isTerminating(scriptState))
+        return true;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 bool ReadableStreamOperations::isReadableStreamDefaultReader(ScriptState* scriptState, ScriptValue value)
 {
+    if (isTerminating(scriptState))
+        return true;
     ASSERT(!value.isEmpty());
 
     if (!value.isObject())
@@ -110,33 +163,47 @@
 
     v8::Local<v8::Value> args[] = { value.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "IsReadableStreamDefaultReader", args);
+    if (isTerminating(scriptState))
+        return true;
     return result.ToLocalChecked()->ToBoolean()->Value();
 }
 
 ScriptPromise ReadableStreamOperations::defaultReaderRead(ScriptState* scriptState, ScriptValue reader)
 {
+    if (isTerminating(scriptState))
+        return ScriptPromise();
     ASSERT(isReadableStreamDefaultReader(scriptState, reader));
 
     v8::Local<v8::Value> args[] = { reader.v8Value() };
     v8::MaybeLocal<v8::Value> result = V8ScriptRunner::callExtra(scriptState, "ReadableStreamDefaultReaderRead", args);
+    if (isTerminating(scriptState))
+        return ScriptPromise();
     return ScriptPromise::cast(scriptState, result.ToLocalChecked());
 }
 
 void ReadableStreamOperations::tee(ScriptState* scriptState, ScriptValue stream, ScriptValue* newStream1, ScriptValue* newStream2)
 {
+    if (isTerminating(scriptState))
+        return;
     DCHECK(isReadableStream(scriptState, stream));
     DCHECK(!isLocked(scriptState, stream));
 
     v8::Local<v8::Value> args[] = { stream.v8Value() };
 
     v8::MaybeLocal<v8::Value> maybeResult = V8ScriptRunner::callExtra(scriptState, "ReadableStreamTee", args);
+    if (isTerminating(scriptState))
+        return;
     ScriptValue result(scriptState, maybeResult.ToLocalChecked());
     DCHECK(result.v8Value()->IsArray());
     v8::Local<v8::Array> branches = result.v8Value().As<v8::Array>();
     DCHECK_EQ(2u, branches->Length());
 
     v8::MaybeLocal<v8::Value> maybeStream1 = branches->Get(scriptState->context(), 0);
+    if (isTerminating(scriptState))
+        return;
     v8::MaybeLocal<v8::Value> maybeStream2 = branches->Get(scriptState->context(), 1);
+    if (isTerminating(scriptState))
+        return;
 
     *newStream1 = ScriptValue(scriptState, maybeStream1.ToLocalChecked());
     *newStream2 = ScriptValue(scriptState, maybeStream2.ToLocalChecked());