Slimming Paint phase 2 compositing algorithm plumbing

Source/core/dom/DocumentLifecycle.cpp

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  * Copyright (C) 2013 Google Inc. All rights reserved.
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  * modification, are permitted provided that the following conditions are
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  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/dom/DocumentLifecycle.h"
 
+#include "platform/RuntimeEnabledFeatures.h"
 #include "wtf/Assertions.h"
 
 namespace blink {
 
 static DocumentLifecycle::DeprecatedTransition* s_deprecatedTransitionStack = 0;
 
 DocumentLifecycle::Scope::Scope(DocumentLifecycle& lifecycle, State finalState)
     : m_lifecycle(lifecycle)
     , m_finalState(finalState)
 {
@@ skipping 121 matching lines @@
         if (state == InPerformLayout)
             return true;
         // We can redundant arrive in the layout clean state. This situation
         // can happen when we call layout recursively and we unwind the stack.
         if (state == LayoutClean)
             return true;
         if (state == StyleClean)
             return true;
         if (state == InCompositingUpdate)
             return true;
+        if (RuntimeEnabledFeatures::slimmingPaintV2Enabled() && state == InPaintInvalidation)

[chrishtr, 2015/08/13 17:28:31]

Also add the paint lifecycle stage in this CL.

[pdr., 2015/08/13 20:54:59]

Done.

As discussed offline, it'll be difficult to do the spv2 transition reusing the
existing compositing lifecycle phase. We now have four new states for
InPaintForSlimmingPaintV2 and InCompositingForSlimmingPaintV2 (and *Clean
versions, respectively). Two phases are not strictly needed but I think they'll
become useful very soon.

+            return true;
         break;
     case InCompositingUpdate:
         return state == CompositingClean;
     case CompositingClean:
         if (state == InStyleRecalc)
             return true;
         if (state == InPreLayout)
             return true;
         if (state == InCompositingUpdate)
             return true;
@@ skipping 41 matching lines @@
 void DocumentLifecycle::ensureStateAtMost(State state)
 {
     ASSERT(state == VisualUpdatePending || state == StyleClean || state == LayoutClean);
     if (m_state <= state)
         return;
     ASSERT(canRewindTo(state));
     m_state = state;
 }
 
 }