Revert "SkRegion: more robust validation"

This reverts commit 711450e948b9900011dc0d474f82bf7bc9913259.

Reason for revert: speculative revert to fix chrome roll.

Original change's description:
> SkRegion: more robust validation
> 
> BUG=oss-fuzz:1864
> Change-Id: I4c3d3c4c7b0717399fe16f227e032682b13ebc74
> Reviewed-on: https://skia-review.googlesource.com/20322
> Reviewed-by: Cary Clark <caryclark@google.com>
> Commit-Queue: Hal Canary <halcanary@google.com>

TBR=halcanary@google.com,caryclark@google.com,reed@google.com

Change-Id: I95cbbf064db6ea7ef74a757bca058ba8de20d87b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: oss-fuzz:1864
Reviewed-on: https://skia-review.googlesource.com/20452
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>

1 files changed, 1 insertions, 17 deletions

diff --git a/src/core/SkRegion.cpp b/src/core/SkRegion.cpp
index b25633b67c..e873ebb453 100644
--- a/src/core/SkRegion.cpp
+++ b/src/core/SkRegion.cpp
@@ -1155,9 +1155,6 @@ static bool validate_run(const int32_t* runs,
     if (rect.fTop == SkRegion::kRunTypeSentinel) {
         return false;  // no rect can contain SkRegion::kRunTypeSentinel
     }
-    if (rect.fTop != givenBounds.fTop) {
-        return false;  // Must not begin with empty span that does not contribute to bounds.
-    }
     do {
         --ySpanCount;
         if (ySpanCount < 0) {
@@ -1167,13 +1164,6 @@ static bool validate_run(const int32_t* runs,
         if (rect.fBottom == SkRegion::kRunTypeSentinel) {
             return false;
         }
-        if (rect.fBottom > givenBounds.fBottom) {
-            return false;  // Must not end with empty span that does not contribute to bounds.
-        }
-        if (rect.fBottom <= rect.fTop) {
-            return false;  // y-intervals must be ordered; rects must be non-empty.
-        }
-
         int32_t xIntervals = *runs++;
         SkASSERT(runs < end);
         if (xIntervals < 0 || runs + 1 + 2 * xIntervals > end) {
@@ -1183,19 +1173,13 @@ static bool validate_run(const int32_t* runs,
         if (intervalCount < 0) {
             return false;  // too many intervals
         }
-        bool firstInterval = true;
-        int32_t lastRight;  // check that x-intervals are distinct and ordered.
         while (xIntervals-- > 0) {
             rect.fLeft = *runs++;
             rect.fRight = *runs++;
             if (rect.fLeft == SkRegion::kRunTypeSentinel ||
-                rect.fRight == SkRegion::kRunTypeSentinel ||
-                rect.fLeft >= rect.fRight ||  // check non-empty rect
-                (!firstInterval && rect.fLeft <= lastRight)) {
+                rect.fRight == SkRegion::kRunTypeSentinel || rect.isEmpty()) {
                 return false;
             }
-            lastRight = rect.fRight;
-            firstInterval = false;
             bounds.join(rect);
         }
         if (*runs++ != SkRegion::kRunTypeSentinel) {