[inspector] don't use v8::Isolate::GetCurrent in V8StackTraceImpl

In inspector code everywhere except V8StackTraceImpl we get pointer to isolate from inspector object or v8::FunctionCallbackInfo. We can avoid usage of v8::Isolate::GetCurrent in V8StackTraceImpl too. It will simplify a little embedder code by removing requirement to have v8::Isolate::Scope before calling to V8InspectorSession::dispatchProtocolMessage.

BUG=v8:5907
R=dgozman@chromium.org

Review-Url: https://codereview.chromium.org/2789593002
Cr-Commit-Position: refs/heads/master@{#44282}

src/inspector/v8-console.cc

@@ -261,7 +261,7 @@ void V8Console::countCallback(const v8::FunctionCallbackInfo<v8::Value>& info) {
   String16 identifier;
   if (title.isEmpty()) {
     std::unique_ptr<V8StackTraceImpl> stackTrace =
-        V8StackTraceImpl::capture(nullptr, 0, 1);
+        V8StackTraceImpl::capture(helper.inspector()->debugger(), 0, 1);
     if (stackTrace && !stackTrace->isEmpty()) {
       identifier = toString16(stackTrace->topSourceURL()) + ":" +
                    String16::fromInteger(stackTrace->topLineNumber());

src/inspector/v8-stack-trace-impl.cc

@@ -40,9 +40,8 @@ V8StackTraceImpl::Frame toFrame(v8::Local<v8::StackFrame> frame,
   int sourceColumn = frame->GetColumn() - 1;
   // TODO(clemensh): Figure out a way to do this translation only right before
   // sending the stack trace over wire.
-  if (wasmTranslation)
-    wasmTranslation->TranslateWasmScriptLocationToProtocolLocation(
-        &scriptId, &sourceLineNumber, &sourceColumn);
+  wasmTranslation->TranslateWasmScriptLocationToProtocolLocation(
+      &scriptId, &sourceLineNumber, &sourceColumn);
   return V8StackTraceImpl::Frame(functionName, scriptId, sourceName,
                                  sourceLineNumber + 1, sourceColumn + 1);
 }
@@ -55,8 +54,7 @@ void toFramesVector(v8::Local<v8::StackTrace> stackTrace,
   int frameCount = stackTrace->GetFrameCount();
   if (frameCount > static_cast<int>(maxStackSize))
     frameCount = static_cast<int>(maxStackSize);
-  WasmTranslation* wasmTranslation =
-      debugger ? debugger->wasmTranslation() : nullptr;
+  WasmTranslation* wasmTranslation = debugger->wasmTranslation();
   for (int i = 0; i < frameCount; i++) {
     v8::Local<v8::StackFrame> stackFrame = stackTrace->GetFrame(i);
     frames.push_back(toFrame(stackFrame, wasmTranslation, contextGroupId));
@@ -118,7 +116,8 @@ std::unique_ptr<V8StackTraceImpl> V8StackTraceImpl::create(
     V8Debugger* debugger, int contextGroupId,
     v8::Local<v8::StackTrace> stackTrace, size_t maxStackSize,
     const String16& description) {
-  v8::Isolate* isolate = v8::Isolate::GetCurrent();
+  DCHECK(debugger);
+  v8::Isolate* isolate = debugger->inspector()->isolate();
   v8::HandleScope scope(isolate);
   std::vector<V8StackTraceImpl::Frame> frames;
   if (!stackTrace.IsEmpty())
@@ -127,7 +126,7 @@ std::unique_ptr<V8StackTraceImpl> V8StackTraceImpl::create(
 
   int maxAsyncCallChainDepth = 1;
   V8StackTraceImpl* asyncCallChain = nullptr;
-  if (debugger && maxStackSize > 1) {
+  if (maxStackSize > 1) {
     asyncCallChain = debugger->currentAsyncCallChain();
     maxAsyncCallChainDepth = debugger->maxAsyncCallChainDepth();
   }
@@ -170,7 +169,8 @@ std::unique_ptr<V8StackTraceImpl> V8StackTraceImpl::create(
 std::unique_ptr<V8StackTraceImpl> V8StackTraceImpl::capture(
     V8Debugger* debugger, int contextGroupId, size_t maxStackSize,
     const String16& description) {
-  v8::Isolate* isolate = v8::Isolate::GetCurrent();
+  DCHECK(debugger);
+  v8::Isolate* isolate = debugger->inspector()->isolate();
   v8::HandleScope handleScope(isolate);
   v8::Local<v8::StackTrace> stackTrace;
   if (isolate->InContext()) {
@@ -270,7 +270,8 @@ V8StackTraceImpl::buildInspectorObjectImpl() const {
 
 std::unique_ptr<protocol::Runtime::StackTrace>
 V8StackTraceImpl::buildInspectorObjectForTail(V8Debugger* debugger) const {
-  v8::HandleScope handleScope(v8::Isolate::GetCurrent());
+  DCHECK(debugger);
+  v8::HandleScope handleScope(debugger->inspector()->isolate());
   // Next call collapses possible empty stack and ensures
   // maxAsyncCallChainDepth.
   std::unique_ptr<V8StackTraceImpl> fullChain = V8StackTraceImpl::create(