[Blink] WebCL support for Crosswalk.

WebCL 1.0 defines a JavaScript binding to the Khronos OpenCL standard
for heterogeneous parallel computing. Its spec is available at:
http://www.khronos.org/registry/webcl/specs/latest/1.0/

This patch includes WebCL basic APIs support, dynamic loading mechanism
etc. WebCL support is controlled by "ENABLE_WEBCL" flag, and it's enabled
by default on Android. If you want to disable with WebCL,
please add "-Denable_webcl=0" when running the "xwalk/gyp_xwalk" before building.

Currently, Intel CPU/GPU, Qualcomm CPU/GPU and Power VR GPU are supported.
But OpenCL library isn't always shipped with device by default, even it supports OpenCL.
For example: Google Nexus series. It requires to install OpenCL library manually.

TEST=WebCL conformances test on Asus MemoPad and Xiaomi3.

Known issue:
1. miss oilpan support.
2. miss cl_khr_gl_sharing extension support.
3. load library in render process.

[email protected], [email protected], [email protected]

BUG=XWALK-4254

[M48: adapted to the following upstream changes:
 - https://codereview.chromium.org/1303153005
 - https://codereview.chromium.org/1362103002
 - https://codereview.chromium.org/1372463002
 - https://codereview.chromium.org/1441573002]

[M49: adapted to the following changes:
WebCL: Only set ENABLE_WEBCL in the relevant files.
WebCL: Remove "config.h" in WebCL Related Implementation and Fix
Compile Error
WebCL: Using gyp to enable or disable WebCL. BUG=XWALK-6200
WebCL: Fix calling convention of callbacks.
WebCL: Build WebCL for all platforms and enable it during runtime.
WebCL: Use the CPU() macro provided by WTF for CPU arch detection.
WebCL: Fix build with component=shared_library.]

[M50: adapted to the following changes:
WebCL: Modified corresponding class to final for warning error
elimation.
WebCL: Change WebCLCallback parent class from RefCounted to
GarbageCollectedFinalized for idl generation rule changed. Now the
upstream generate callbakc interface with oilpan support.
WebCL: Due to WebCLCallback is oilpan supported, Modifined RefPtr to
Persistent or Member, Vector to HeapVector/PersistentHeapVector in
corresponding non-garbage-collected class to elimate compile error.]

third_party/WebKit/Source/bindings/core/v8/ExceptionState.cpp

@@ -71,6 +71,18 @@ void ExceptionState::throwDOMException(const ExceptionCode& ec, const String& me
     setException(V8ThrowException::createDOMException(m_isolate, ec, processedMessage, m_creationContext));
 }
 
+void ExceptionState::throwWebCLException(const ExceptionCode& ec, const String& message)
+{
+    ASSERT(ec);
+    ASSERT(m_isolate);
+    ASSERT(!m_creationContext.IsEmpty());
+
+    m_code = ec;
+    String processedMessage = addExceptionContext(message);
+    m_message = processedMessage;
+    setException(V8ThrowException::createWebCLException(m_isolate, ec, message, processedMessage, m_creationContext));
+}
+
 void ExceptionState::throwSecurityError(const String& sanitizedMessage, const String& unsanitizedMessage)
 {
     ASSERT(m_isolate);

third_party/WebKit/Source/bindings/core/v8/ExceptionState.h

@@ -82,6 +82,7 @@ class CORE_EXPORT ExceptionState {
         , m_isolate(isolate) { ASSERT(m_context == ConstructionContext || m_context == EnumerationContext || m_context == IndexedSetterContext || m_context == IndexedGetterContext || m_context == IndexedDeletionContext); }
 
     virtual void throwDOMException(const ExceptionCode&, const String& message);
+    virtual void throwWebCLException(const ExceptionCode&, const String& message);
     virtual void throwTypeError(const String& message);
     virtual void throwSecurityError(const String& sanitizedMessage, const String& unsanitizedMessage = String());
     virtual void throwRangeError(const String& message);

third_party/WebKit/Source/bindings/core/v8/V8ThrowException.cpp

@@ -27,8 +27,11 @@
 #include "bindings/core/v8/BindingSecurity.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8DOMException.h"
+#include "bindings/core/v8/V8WebCLException.h"
 #include "core/dom/DOMException.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/webcl/WebCLException.h"
+#include "wtf/RefPtr.h"
 
 namespace blink {
 
@@ -46,6 +49,20 @@ static void domExceptionStackSetter(v8::Local<v8::Name> name, v8::Local<v8::Valu
     ALLOW_UNUSED_LOCAL(unused);
 }
 
+static void webclExceptionStackGetter(v8::Local<v8::Name> name, const v8::PropertyCallbackInfo<v8::Value>& info)
+{
+    v8::Isolate* isolate = info.GetIsolate();
+    v8::Local<v8::Value> value;
+    if (info.Data().As<v8::Object>()->Get(isolate->GetCurrentContext(), v8AtomicString(isolate, "stack")).ToLocal(&value))
+        v8SetReturnValue(info, value);
+}
+
+static void webclExceptionStackSetter(v8::Local<v8::Name> name, v8::Local<v8::Value> value, const v8::PropertyCallbackInfo<void>& info)
+{
+    v8::Maybe<bool> unused = info.Data().As<v8::Object>()->Set(info.GetIsolate()->GetCurrentContext(), v8AtomicString(info.GetIsolate(), "stack"), value);
+    ALLOW_UNUSED_LOCAL(unused);
+}
+
 v8::Local<v8::Value> V8ThrowException::createDOMException(v8::Isolate* isolate, int ec, const String& sanitizedMessage, const String& unsanitizedMessage, const v8::Local<v8::Object>& creationContext)
 {
     if (ec <= 0 || isolate->IsExecutionTerminating())
@@ -96,6 +113,42 @@ v8::Local<v8::Value> V8ThrowException::createDOMException(v8::Isolate* isolate,
     return exception;
 }
 
+v8::Local<v8::Value> V8ThrowException::createWebCLException(v8::Isolate* isolate, int ec, const String& name, const String& message, const v8::Local<v8::Object>& creationContext)
+{
+    if (ec <= 0 || isolate->IsExecutionTerminating())
+        return v8Undefined();
+
+    v8::Local<v8::Object> sanitizedCreationContext = creationContext;
+
+    ScriptState* scriptState = ScriptState::from(creationContext->CreationContext());
+    Frame* frame = toFrameIfNotDetached(scriptState->context());
+    if (!frame || !BindingSecurity::shouldAllowAccessToFrame(isolate, callingDOMWindow(isolate), frame, DoNotReportSecurityError)) {
+        scriptState = ScriptState::current(isolate);
+        sanitizedCreationContext = scriptState->context()->Global();
+    }
+
+    v8::TryCatch tryCatch(isolate);
+
+    RefPtr<WebCLException> webclException = WebCLException::create(ec, name, message);
+    v8::Local<v8::Value> exception = toV8(webclException, creationContext, isolate);
+
+    if (tryCatch.HasCaught()) {
+        ASSERT(exception.IsEmpty());
+        return tryCatch.Exception();
+    }
+    ASSERT(!exception.IsEmpty());
+
+    // Attach an Error object to the WebCLException. This is then lazily used to get the stack value.
+    v8::Local<v8::Value> error = v8::Exception::Error(v8String(isolate, webclException->message()));
+    ASSERT(!error.IsEmpty());
+    v8::Local<v8::Object> exceptionObject = exception.As<v8::Object>();
+    v8::Maybe<bool> result = exceptionObject->SetAccessor(isolate->GetCurrentContext(), v8AtomicString(isolate, "stack"), webclExceptionStackGetter, webclExceptionStackSetter, v8::MaybeLocal<v8::Value>(error));
+    ASSERT_UNUSED(result, result.FromJust());
+    V8HiddenValue::setHiddenValue(scriptState, exceptionObject, V8HiddenValue::error(isolate), error);
+
+    return exception;
+}
+
 v8::Local<v8::Value> V8ThrowException::createGeneralError(v8::Isolate* isolate, const String& message)
 {
     return v8::Exception::Error(v8String(isolate, message.isNull() ? "Error" : message));

third_party/WebKit/Source/bindings/core/v8/V8ThrowException.h

@@ -42,6 +42,8 @@ class CORE_EXPORT V8ThrowException {
     }
     static v8::Local<v8::Value> createDOMException(v8::Isolate*, int, const String& sanitizedMessage, const String& unsanitizedMessage, const v8::Local<v8::Object>& creationContext);
 
+    static v8::Local<v8::Value> createWebCLException(v8::Isolate*, int, const String& name, const String& message, const v8::Local<v8::Object>& creationContext);
+
     static v8::Local<v8::Value> throwException(v8::Local<v8::Value>, v8::Isolate*);
 
     static v8::Local<v8::Value> createGeneralError(v8::Isolate*, const String&);