Fix PDFBrowserTest.Basic crash.

Lock pixels before using them

BUG=446347

Review URL: https://codereview.chromium.org/850043002

Cr-Commit-Position: refs/heads/master@{#311577}

chrome/browser/ui/pdf/pdf_browsertest.cc

@@ -26,8 +26,7 @@ namespace {
 
 // Tests basic PDF rendering.  This can be broken depending on bad merges with
 // the vendor, so it's important that we have basic sanity checking.
-// TODO(eustas): This is failing on CROS offical build. crbug.com/446347.
-#if defined(GOOGLE_CHROME_BUILD) && defined(OS_LINUX) && !defined(OS_CHROMEOS)
+#if defined(GOOGLE_CHROME_BUILD) && defined(OS_LINUX)
 #define MAYBE_Basic Basic
 #else
 #define MAYBE_Basic DISABLED_Basic

chrome/browser/ui/pdf/pdf_browsertest_base.cc

@@ -133,6 +133,7 @@ void PDFBrowserTest::CopyFromBackingStoreCallback(
       gfx::PNGCodec::FORMAT_BGRA, &decoded, &w, &h));
   int32* ref_pixels = reinterpret_cast<int32*>(&decoded[0]);
 
+  SkAutoLockPixels lock_image(bitmap);
   int32* pixels = static_cast<int32*>(bitmap.getPixels());
 
   // Get the background color, and use it to figure out the x-offsets in