Revert "Revert "Support multiple DOM isolates and tweak devtools frontend to better handle large #s…

Source/bindings/core/dart/DartController.cpp

Index: Source/bindings/core/dart/DartController.cpp
diff --git a/Source/bindings/core/dart/DartController.cpp b/Source/bindings/core/dart/DartController.cpp
index d6e56c4f297931cc458f9b013bf8f77b7dc15f04..2546d2523a45f209096ba4b5c39bd91ada6ea4b1 100644
--- a/Source/bindings/core/dart/DartController.cpp
+++ b/Source/bindings/core/dart/DartController.cpp
@@ -333,10 +333,10 @@ void DartController::clearWindowShell()
     DART_START_TIMER();
     initVMIfNeeded();
     DART_RECORD_TIMER("clearWindowShell::initVM took");
-    m_documentsWithDart.clear();
-    if (m_loader) {
-        m_loader = nullptr;
-    }
+    m_loaders.clear();
+    m_usedNames.clear();
+    m_isolateNames.clear();
+    m_mainLoader.clear();
 
     // Due to synchronous dispatch, we may be in an isolate corresponding to another frame.
     // If so, exit here but re-enter before returning.
@@ -749,17 +749,16 @@ void DartController::loadAndRunScript(const String& url, Dart_Isolate isolate, P
 
     // Invoke only if this is the main document.
     ASSERT(scriptInfo->ownerDocument() == document);
-
-    ASSERT(m_loader);
+    RefPtr<DartApplicationLoader> loader = m_loaders.get(isolate);
+    ASSERT(loader);
     // Due to deferred loading we might already be running Dart code on
     // an isolate and the library tag handler callback could result in a call
     // to this code, we skip the Enter/Exit Isolate calls in that case.
     if (isolate == Dart_CurrentIsolate()) {
-        m_loader->load(scriptInfo);
+        loader->load(scriptInfo);
     } else {
-        Dart_EnterIsolate(isolate);
-        m_loader->load(scriptInfo);
-        Dart_ExitIsolate();
+        DartIsolateScope scope(isolate);
+        loader->load(scriptInfo);
     }
 
     DART_RECORD_TIMER("DartController::loadAndRunScript took");
@@ -789,56 +788,40 @@ void DartController::evaluate(const ScriptSourceCode& sourceCode, ScriptLoader*
         return;
     }
 
-    Document* owner = scriptInfo->ownerDocument();
-    if (m_documentsWithDart.contains(owner)) {
+    RefPtr<DartApplicationLoader> currentLoader;
+
+    // HTML Import case.
+    if (m_mainLoader && document != scriptInfo->ownerDocument() && !m_mainLoader->uninitialized()) {
         int line = scriptInfo->startLineNumber().zeroBasedInt();
-        DartUtilities::reportProblem(owner, "Only one Dart script tag allowed per document", line);
+        DartUtilities::reportProblem(document, "Inline Darts scripts not supported after main script is invoked.", line);
         return;
     }
-    m_documentsWithDart.add(owner);
-
-    if (m_loader) {
-        if (m_loader->running()) {
-            // Main has already been invoked.
-            String scriptURL = scriptInfo->sourceAttributeValue();
-
-            // Enforce that no new code is loaded. We've already invoked main at this point.
-            // Any referenced code must already be in the isolate.
-            if (scriptURL.isEmpty()) {
-                int line = scriptInfo->startLineNumber().zeroBasedInt();
-                DartUtilities::reportProblem(document, "Inline Darts scripts not supported after main script is invoked.", line);
-            } else {
-                m_loader->validateUrlLoaded(scriptURL);
-            }
-            return;
+    if (!m_mainLoader || (!m_mainLoader->uninitialized() && document == scriptInfo->ownerDocument())) {
+        // FIXME: perhaps if loader->validateUrlLoaded(scriptURL) has been
+        // called we are actually good to use the existing loader?
+        currentLoader = DartApplicationLoader::create(document, true);
+        if (!m_mainLoader) {
+            m_mainLoader = currentLoader;
         }
-        if (m_loader->error()) {
-            return;
-        }
-    }
-
-    if (!m_loader) {
-        m_loader = DartApplicationLoader::create(document, true);
+    } else {
+        currentLoader = m_mainLoader;
     }
 
     DART_RECORD_TIMER("evaluate::prep for loading took");
     if (document == scriptInfo->ownerDocument()) {
         String url = scriptInfo->url();
-        // FIXME: This should be the first DOM enabled isolate. There is a race condition
-        // however - m_loader above won't catch this if it hasn't been set yet.
-        // This problem goes away once we map each script to a separate isolate.
-        if (!m_isolates.isEmpty())
-            return;
         DART_RECORD_TIMER("evaluate before createIsolate");
         DEFINE_STATIC_LOCAL(const char*, packageRoot, (getenv("DART_PACKAGE_ROOT")));
         Dart_Isolate isolate = createDOMEnabledIsolate(url, "main", packageRoot, document);
+        m_loaders.add(isolate, currentLoader);
         DART_RECORD_TIMER("evaluate after createIsolate");
         RefPtr<DartDomLoadCallback> callback = adoptRef(new DartDomLoadCallback(this, url, isolate, document, scriptInfo));
         Dart_ExitIsolate();
-        m_loader->processRequests(isolate, sourceCode, callback);
+        currentLoader->processRequests(isolate, sourceCode, callback);
         DART_RECORD_TIMER("evaluate process request took");
     } else {
-        m_loader->addRequest(scriptInfo);
+        // Add all HTML import scripts into the first loader.
+        m_mainLoader->addRequest(scriptInfo);
     }
     DART_RECORD_TIMER("evaluate took");
 }
@@ -930,7 +913,7 @@ DartScriptState* DartController::lookupScriptStateFromLibraryIdMap(Dart_Isolate
     DartScriptState* scriptState;
     if (libraryIter == libraryIdMap->end()) {
         V8ScriptState* v8ScriptState = V8ScriptState::from(v8Context);
-        RefPtr<DartScriptState> scriptStatePtr = DartScriptState::create(isolate, libraryId, v8ScriptState);
+        RefPtr<DartScriptState> scriptStatePtr = DartScriptState::create(isolate, libraryId, v8ScriptState, isolateName(isolate));
         libraryIdMap->set(libraryIdKey, scriptStatePtr);
         scriptState = scriptStatePtr.get();
     } else {
@@ -940,6 +923,33 @@ DartScriptState* DartController::lookupScriptStateFromLibraryIdMap(Dart_Isolate
     return scriptState;
 }
 
+String DartController::isolateName(Dart_Isolate isolate)
+{
+    if (m_isolateNames.contains(isolate)) {
+        return m_isolateNames.get(isolate);
+    }
+    String fileName("");
+    String name;
+    if (m_loaders.contains(isolate)) {
+        const KURL& scriptUrl = m_loaders.get(isolate)->scriptUrl();
+        if (scriptUrl.isValid()) {
+            String lastPathComponent = scriptUrl.lastPathComponent();
+            if (!lastPathComponent.isEmpty()) {
+                fileName = scriptUrl.lastPathComponent();
+            }
+        }
+    }
+    name = fileName;
+    int i = 2;
+    while (m_usedNames.contains(name)) {
+        name = String::format("%s[%d]", fileName.utf8().data(), i);
+        i++;
+    }
+    m_isolateNames.add(isolate, name);
+    m_usedNames.add(name);
+    return name;
+}
+
 void DartController::collectScriptStatesForIsolate(Dart_Isolate isolate, v8::Handle<v8::Context> v8Context, Vector<DartScriptState*>& result)
 {
     if (!isolate)