[chromium] Always use border texels on platforms using pageScaleDelta

https://bugs.webkit.org/show_bug.cgi?id=74226

Patch by Alexandre Elias <aelias@google.com> on 2011-12-21
Reviewed by James Robinson.

On platforms where the root layer can be zoomed in at draw time
(pageScaleDelta), we want to turn on border texels in order for
scaling to use GL_LINEAR instead of GL_NEAREST.

No new tests. (Flag flip.)

* platform/graphics/chromium/TiledLayerChromium.cpp:
(WebCore::TiledLayerChromium::prepareToUpdate):

git-svn-id: svn://svn.chromium.org/blink/trunk@103490 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/WebCore/ChangeLog

+2011-12-21  Alexandre Elias  <aelias@google.com>
+
+        [chromium] Always use border texels on platforms using pageScaleDelta
+        https://bugs.webkit.org/show_bug.cgi?id=74226
+
+        Reviewed by James Robinson.
+
+        On platforms where the root layer can be zoomed in at draw time
+        (pageScaleDelta), we want to turn on border texels in order for
+        scaling to use GL_LINEAR instead of GL_NEAREST.
+
+        No new tests. (Flag flip.)
+
+        * platform/graphics/chromium/TiledLayerChromium.cpp:
+        (WebCore::TiledLayerChromium::prepareToUpdate):
+
 2011-12-21  Dale Curtis  <dalecurtis@chromium.org>
 
         [chromium] Scale audio, video tags in MediaDocument to fit in window.

third_party/WebKit/Source/WebCore/platform/graphics/chromium/TiledLayerChromium.cpp

@@ -430,8 +430,16 @@ void TiledLayerChromium::prepareToUpdateTiles(bool idle, int left, int top, int
 
 void TiledLayerChromium::prepareToUpdate(const IntRect& contentRect)
 {
-    if (!m_tiler)
-        createTiler(isNonCompositedContent() ? CCLayerTilingData::NoBorderTexels : CCLayerTilingData::HasBorderTexels);
+    if (!m_tiler) {
+        CCLayerTilingData::BorderTexelOption borderTexelOption;
+#if OS(ANDROID)
+        // Always want border texels and GL_LINEAR due to pinch zoom.
+        borderTexelOption = CCLayerTilingData::HasBorderTexels;
+#else
+        borderTexelOption = isNonCompositedContent() ? CCLayerTilingData::NoBorderTexels : CCLayerTilingData::HasBorderTexels;
+#endif
+        createTiler(borderTexelOption);
+    }
 
     ASSERT(m_tiler);