Reland: Remove unsafe cast from ImageTransportSurfaceOverlayMac::ScheduleCALayer.

gpu/ipc/service/image_transport_surface_overlay_mac.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/ipc/service/image_transport_surface_overlay_mac.h"
 
 #include <CoreGraphics/CoreGraphics.h>
 #include <IOSurface/IOSurface.h>
 #include <OpenGL/CGLRenderers.h>
 #include <OpenGL/CGLTypes.h>
@@ skipping 145 matching lines @@
   params.io_surface = io_surface;
   params.pixel_size = size;
   params.scale_factor = scale_factor;
   params.latency_info = std::move(latency_info);
   params.result = gfx::SwapResult::SWAP_ACK;
 
   for (auto& query : ca_layer_in_use_queries_) {
     gpu::TextureInUseResponse response;
     response.texture = query.texture;
     bool in_use = false;
-    if (query.image) {
-      gl::GLImageIOSurface* io_surface_image =
-          static_cast<gl::GLImageIOSurface*>(query.image.get());
+    gl::GLImageIOSurface* io_surface_image =
+        gl::GLImageIOSurface::FromGLImage(query.image.get());
+    if (io_surface_image) {
       in_use = io_surface_image->CanCheckIOSurfaceIsInUse() &&
                IOSurfaceIsInUse(io_surface_image->io_surface());
     }
     response.in_use = in_use;
     params.in_use_responses.push_back(std::move(response));
   }
   ca_layer_in_use_queries_.clear();
 
   stub_->SendSwapBuffersCompleted(params);
 }
@@ skipping 134 matching lines @@
     const gfx::Rect& pixel_frame_rect,
     const gfx::RectF& crop_rect) {
   if (transform != gfx::OVERLAY_TRANSFORM_NONE) {
     DLOG(ERROR) << "Invalid overlay plane transform.";
     return false;
   }
   if (z_order) {
     DLOG(ERROR) << "Invalid non-zero Z order.";
     return false;
   }
+  gl::GLImageIOSurface* io_surface_image =
+      gl::GLImageIOSurface::FromGLImage(image);
+  if (!io_surface_image) {
+    DLOG(ERROR) << "Not an IOSurface image.";
+    return false;
+  }
   return ca_layer_tree_coordinator_->SetPendingGLRendererBackbuffer(
-      static_cast<gl::GLImageIOSurface*>(image)->io_surface());
+      io_surface_image->io_surface());
 }
 
 bool ImageTransportSurfaceOverlayMac::ScheduleCALayer(
     gl::GLImage* contents_image,
     const gfx::RectF& contents_rect,
     float opacity,
     unsigned background_color,
     unsigned edge_aa_mask,
     const gfx::RectF& rect,
     bool is_clipped,
     const gfx::RectF& clip_rect,
     const gfx::Transform& transform,
     int sorting_context_id,
     unsigned filter) {
   base::ScopedCFTypeRef<IOSurfaceRef> io_surface;
   base::ScopedCFTypeRef<CVPixelBufferRef> cv_pixel_buffer;
-  if (contents_image) {
-    gl::GLImageIOSurface* io_surface_image =
-        static_cast<gl::GLImageIOSurface*>(contents_image);
+  gl::GLImageIOSurface* io_surface_image =
+      gl::GLImageIOSurface::FromGLImage(contents_image);
+  if (io_surface_image) {

[ccameron, 2016/06/30 03:57:55]

We should have an error message, for instance:

if (contents_image) {
  gl::GLImageIOSurface* io_surface_image =
    gl::GLImageIOSurface::FromGLImage(contents_image);
  if (!io_surface_image) {
    DLOG(ERROR) << "Cannot schedule CALayer with non-IOSurface GLImage";
    return false
  }
  io_surface = io_surface_image->io_surface();
  cv_pixel_buffer = io_surface_image->cv_pixel_buffer();
}

[piman, 2016/06/30 04:03:18]

Done.

     io_surface = io_surface_image->io_surface();
     cv_pixel_buffer = io_surface_image->cv_pixel_buffer();
   }
   return ca_layer_tree_coordinator_->GetPendingCARendererLayerTree()
       ->ScheduleCALayer(is_clipped, gfx::ToEnclosingRect(clip_rect),
                         sorting_context_id, transform, io_surface,
                         cv_pixel_buffer, contents_rect,
                         gfx::ToEnclosingRect(rect), background_color,
                         edge_aa_mask, opacity, filter);
 }
@@ skipping 32 matching lines @@
   gl_renderer_id_ = context_renderer_id & kCGLRendererIDMatchingMask;
 
   // Post a task holding a reference to the new GL context. The reason for
   // this is to avoid creating-then-destroying the context for every image
   // transport surface that is observing the GPU switch.
   base::MessageLoop::current()->PostTask(
       FROM_HERE, base::Bind(&IOSurfaceContextNoOp, context_on_new_gpu));
 }
 
 }  // namespace gpu