Skip batch iteration in GrDrawTarget::forwardCombine when the max look ahead is 0

src/gpu/GrDrawTarget.cpp

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDrawTarget.h"
 
 #include "GrAppliedClip.h"
@@ skipping 553 matching lines @@
     } else {
         GrBATCH_INFO("\t\tFirstBatch\n");
     }
     GR_AUDIT_TRAIL_BATCHING_RESULT_NEW(fAuditTrail, batch);
     fRecordedBatches.emplace_back(RecordedBatch{sk_ref_sp(batch), clippedBounds});
     fLastFullClearBatch = nullptr;
     return batch;
 }
 
 void GrDrawTarget::forwardCombine() {
+    if (fMaxBatchLookahead <= 0) {
+        return;
+    }
     for (int i = 0; i < fRecordedBatches.count() - 2; ++i) {
         GrBatch* batch = fRecordedBatches[i].fBatch.get();
         const SkRect& batchBounds = fRecordedBatches[i].fClippedBounds;
         int maxCandidateIdx = SkTMin(i + fMaxBatchLookahead, fRecordedBatches.count() - 1);
         int j = i + 1;
         while (true) {
             GrBatch* candidate = fRecordedBatches[j].fBatch.get();
             // We cannot continue to search if the render target changes
             if (candidate->renderTargetUniqueID() != batch->renderTargetUniqueID()) {
                 GrBATCH_INFO("\t\tBreaking because of (%s, B%u) Rendertarget\n",
@@ skipping 29 matching lines @@
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 void GrDrawTarget::clearStencilClip(const SkIRect& rect, bool insideClip, GrRenderTarget* rt) {
     GrBatch* batch = new GrClearStencilClipBatch(rect, insideClip, rt);
     this->recordBatch(batch, batch->bounds());
     batch->unref();
 }