Replace scaled bitmap if entry already exist in cache.

BUG=skia:2251
R=reed@google.com

Author: reveman@chromium.org

Review URL: https://codereview.chromium.org/185263009

git-svn-id: http://skia.googlecode.com/svn/trunk@13667 2bbb7eff-a529-9590-31e7-b0007b416f81

2 files changed, 16 insertions, 5 deletions

diff --git a/src/core/SkScaledImageCache.cpp b/src/core/SkScaledImageCache.cpp
index f0f34ccbf1..c436417f28 100644
--- a/src/core/SkScaledImageCache.cpp
+++ b/src/core/SkScaledImageCache.cpp
@@ -425,6 +425,7 @@ SkScaledImageCache::ID* SkScaledImageCache::addAndLock(SkScaledImageCache::Rec*
     if (NULL != existing) {
         // Since we already have a matching entry, just delete the new one and return.
         // Call sites cannot assume the passed in object will live past this call.
+        existing->fBitmap = rec->fBitmap;
         SkDELETE(rec);
         return rec_to_id(existing);
     }
diff --git a/tests/ImageCacheTest.cpp b/tests/ImageCacheTest.cpp
index 65c9068853..43a5e70f23 100644
--- a/tests/ImageCacheTest.cpp
+++ b/tests/ImageCacheTest.cpp
@@ -105,17 +105,27 @@ DEF_TEST(ImageCache, reporter) {
 
 DEF_TEST(ImageCache_doubleAdd, r) {
     // Adding the same key twice should be safe.
-    SkScaledImageCache cache(1024);
+    SkScaledImageCache cache(4096);
 
     SkBitmap original;
     original.allocN32Pixels(40, 40);
 
-    SkBitmap scaled;
-    scaled.allocN32Pixels(20, 20);
+    SkBitmap scaled1;
+    scaled1.allocN32Pixels(20, 20);
 
-    SkScaledImageCache::ID* id1 = cache.addAndLock(original, 0.5f, 0.5f, scaled);
-    SkScaledImageCache::ID* id2 = cache.addAndLock(original, 0.5f, 0.5f, scaled);
+    SkBitmap scaled2;
+    scaled2.allocN32Pixels(20, 20);
+
+    SkScaledImageCache::ID* id1 = cache.addAndLock(original, 0.5f, 0.5f, scaled1);
+    SkScaledImageCache::ID* id2 = cache.addAndLock(original, 0.5f, 0.5f, scaled2);
     // We don't really care if id1 == id2 as long as unlocking both works.
     cache.unlock(id1);
     cache.unlock(id2);
+
+    SkBitmap tmp;
+    // Lookup should return the value that was added last.
+    SkScaledImageCache::ID* id = cache.findAndLock(original, 0.5f, 0.5f, &tmp);
+    REPORTER_ASSERT(r, NULL != id);
+    REPORTER_ASSERT(r, tmp.getGenerationID() == scaled2.getGenerationID());
+    cache.unlock(id);
 }