Implement WEBGL_shared_resources

Source/core/html/canvas/WebGLFramebuffer.cpp

Index: Source/core/html/canvas/WebGLFramebuffer.cpp
diff --git a/Source/core/html/canvas/WebGLFramebuffer.cpp b/Source/core/html/canvas/WebGLFramebuffer.cpp
index 4d622cfaca290131702086366d500cdc83b34d92..bd44076c72748049c05f2eaef7601e89c3570814 100644
--- a/Source/core/html/canvas/WebGLFramebuffer.cpp
+++ b/Source/core/html/canvas/WebGLFramebuffer.cpp
@@ -424,7 +424,7 @@ GC3Denum WebGLFramebuffer::getColorBufferFormat() const
     return attachment->getFormat();
 }
 
-GC3Denum WebGLFramebuffer::checkStatus(const char** reason) const
+GC3Denum WebGLFramebuffer::checkStatus(WebGLRenderingContext* context, WebGLSharedObject::AcquireMode neededAccessMode, const char** reason) const
 {
     unsigned int count = 0;
     GC3Dsizei width = 0, height = 0;
@@ -439,6 +439,9 @@ GC3Denum WebGLFramebuffer::checkStatus(const char** reason) const
             *reason = "attachment is not valid";
             return GraphicsContext3D::FRAMEBUFFER_UNSUPPORTED;
         }
+        WebGLSharedObject* object = attachment->getObject();
+        if (object && !object->isAcquiredForContext(context, neededAccessMode, true, 0, reason))
+            return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
         if (!attachment->getFormat()) {
             *reason = "attachment is an unsupported format";
             return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
@@ -481,9 +484,9 @@ GC3Denum WebGLFramebuffer::checkStatus(const char** reason) const
     return GraphicsContext3D::FRAMEBUFFER_COMPLETE;
 }
 
-bool WebGLFramebuffer::onAccess(GraphicsContext3D* context3d, const char** reason)
+bool WebGLFramebuffer::onAccess(WebGLRenderingContext* context, WebGLSharedObject::AcquireMode neededAccessMode, const char** reason)
 {
-    if (checkStatus(reason) != GraphicsContext3D::FRAMEBUFFER_COMPLETE)
+    if (checkStatus(context, neededAccessMode, reason) != GraphicsContext3D::FRAMEBUFFER_COMPLETE)
         return false;
     return true;
 }