Apply script preprocessor to Web page scripts only.

Source/bindings/v8/ScriptDebugServer.cpp

Index: Source/bindings/v8/ScriptDebugServer.cpp
diff --git a/Source/bindings/v8/ScriptDebugServer.cpp b/Source/bindings/v8/ScriptDebugServer.cpp
index 6678fdd95883da823b24b7ea06323257ad3c7bb7..9b938ac0b0566a1ab36b82e5166bf7d625b9d5cf 100644
--- a/Source/bindings/v8/ScriptDebugServer.cpp
+++ b/Source/bindings/v8/ScriptDebugServer.cpp
@@ -41,6 +41,7 @@
 #include "bindings/v8/V8RecursionScope.h"
 #include "core/inspector/ScriptDebugListener.h"
 #include "wtf/StdLibExtras.h"
+#include "wtf/StringExtras.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
@@ -85,6 +86,7 @@ v8::Local<v8::Value> ScriptDebugServer::callDebuggerMethod(const char* functionN
 class ScriptDebugServer::ScriptPreprocessor {
     WTF_MAKE_NONCOPYABLE(ScriptPreprocessor);
 public:
+
     explicit ScriptPreprocessor(const String& preprocessorScript)
     {
         v8::HandleScope scope;
@@ -137,7 +139,13 @@ public:
 
         if (resultValue->IsString()) {
             v8::String::Utf8Value utf8Value(resultValue);
-            return String::fromUTF8(*utf8Value, utf8Value.length());
+
+            String preprocessed = String::fromUTF8(*utf8Value, utf8Value.length());
+            // Zero bytes crash the page if we are preprocessing injectedScripts
+            if (preprocessed.length() == 0)
+                return sourceCode;
+
+            return preprocessed;
         }
 
         return sourceCode;
@@ -458,7 +466,12 @@ void ScriptDebugServer::handleV8DebugEvent(const v8::Debug::EventDetails& eventD
             if (!m_scriptPreprocessor)
                 return;
 
+            // Don't preprocess debugger scripts or content scripts
+            if (V8PerContextDebugData::isSystemScope(eventContext) || V8PerContextDebugData::contextCategory(eventContext) == "injected")

[pfeldman, 2013/05/01 07:33:55]

Please introduce constant for this so that we could track where it is set. Also,
can we make injected contexts have system scope instead?

+                return;
+
             OwnPtr<ScriptPreprocessor> preprocessor(m_scriptPreprocessor.release());
+
             v8::Local<v8::Context> debugContext = v8::Debug::GetDebugContext();
             v8::Context::Scope contextScope(debugContext);
             v8::Handle<v8::Function> getScriptSourceFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("getScriptSource")));
@@ -469,8 +482,13 @@ void ScriptDebugServer::handleV8DebugEvent(const v8::Debug::EventDetails& eventD
             v8::Handle<v8::Value> argv1[] = { eventDetails.GetEventData() };
             v8::Handle<v8::Value> scriptName = getScriptNameFunction->Call(m_debuggerScript.get(), 1, argv1);
 
+            v8::String::Utf8Value scriptNameUtf8Value(scriptName);
+            String scriptNameString = String::fromUTF8(*scriptNameUtf8Value, scriptNameUtf8Value.length());
+            if (scriptNameString.contains("data:text/html,chromewebdata"))

[pfeldman, 2013/05/01 07:33:55]

You can't say "chromewebdata" from blink which is presumable Chrome-unaware.
Same thing, can it be system?

+                return;
+
             v8::Handle<v8::Function> setScriptSourceFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("setScriptSource")));
-            String patchedScript = preprocessor->preprocessSourceCode(toWebCoreStringWithUndefinedOrNullCheck(script), toWebCoreStringWithUndefinedOrNullCheck(scriptName));
+            String patchedScript = preprocessor->preprocessSourceCode(toWebCoreStringWithUndefinedOrNullCheck(script), scriptNameString);
 
             v8::Handle<v8::Value> argv2[] = { eventDetails.GetEventData(), v8String(patchedScript, debugContext->GetIsolate()) };
             setScriptSourceFunction->Call(m_debuggerScript.get(), 2, argv2);