Make SkSmallAllocator obey the RAII invariants and move to heap structures when needed.

The biggest change is to the API which allowed code to bypass the
destruction invariants. This destruction bypass feature was needed in
only one use, and is totally encapsulated using createWithIniterT.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2488523003

Committed: https://skia.googlesource.com/skia/+/d5dc657b8c3ac916f98005dafdedafe02f023449
Committed: https://skia.googlesource.com/skia/+/c18b5f8f57a4efc5d5d1e399ed8bd3bd02c592ab
Review-Url: https://codereview.chromium.org/2488523003

1 files changed, 15 insertions, 6 deletions

diff --git a/tests/LayerDrawLooperTest.cpp b/tests/LayerDrawLooperTest.cpp
index 4897fd2884..7b3aa29883 100644
--- a/tests/LayerDrawLooperTest.cpp
+++ b/tests/LayerDrawLooperTest.cpp
@@ -60,8 +60,11 @@ static void test_frontToBack(skiatest::Reporter* reporter) {
     SkPaint paint;
     auto looper(looperBuilder.detach());
     SkSmallAllocator<1, 32> allocator;
-    void* buffer = allocator.reserveT<SkDrawLooper::Context>(looper->contextSize());
-    SkDrawLooper::Context* context = looper->createContext(&canvas, buffer);
+    SkDrawLooper::Context* context = allocator.createWithIniter(
+        looper->contextSize(),
+        [&](void* buffer) {
+            return looper->createContext(&canvas, buffer);
+        });
 
     // The back layer should come first.
     REPORTER_ASSERT(reporter, context->next(&canvas, &paint));
@@ -100,8 +103,11 @@ static void test_backToFront(skiatest::Reporter* reporter) {
     SkPaint paint;
     auto looper(looperBuilder.detach());
     SkSmallAllocator<1, 32> allocator;
-    void* buffer = allocator.reserveT<SkDrawLooper::Context>(looper->contextSize());
-    SkDrawLooper::Context* context = looper->createContext(&canvas, buffer);
+    SkDrawLooper::Context* context = allocator.createWithIniter(
+        looper->contextSize(),
+        [&](void* buffer) {
+            return looper->createContext(&canvas, buffer);
+        });
 
     // The back layer should come first.
     REPORTER_ASSERT(reporter, context->next(&canvas, &paint));
@@ -140,8 +146,11 @@ static void test_mixed(skiatest::Reporter* reporter) {
     SkPaint paint;
     sk_sp<SkDrawLooper> looper(looperBuilder.detach());
     SkSmallAllocator<1, 32> allocator;
-    void* buffer = allocator.reserveT<SkDrawLooper::Context>(looper->contextSize());
-    SkDrawLooper::Context* context = looper->createContext(&canvas, buffer);
+    SkDrawLooper::Context* context = allocator.createWithIniter(
+        looper->contextSize(),
+        [&](void* buffer) {
+            return looper->createContext(&canvas, buffer);
+        });
 
     // The back layer should come first.
     REPORTER_ASSERT(reporter, context->next(&canvas, &paint));