webgl: Zero-initialize the SyncToken before calling GenSyncTokenCHROMIUM

third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp

Index: third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp b/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
index 4b8eeaf947af65d0af16af89bf08a1be0ddc4cd5..97092c30aee5a66bc44e20fd4d913e81c630ab1a 100644
--- a/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
+++ b/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
@@ -30,6 +30,7 @@
 
 #include "platform/graphics/gpu/DrawingBuffer.h"
 
+#include "gpu/GLES2/gl2extchromium.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "gpu/command_buffer/common/capabilities.h"
 #include "platform/RuntimeEnabledFeatures.h"
@@ -569,7 +570,7 @@ bool DrawingBuffer::copyToPlatformTexture(gpu::gles2::GLES2Interface* gl, GLuint
     const GLuint64 fenceSync = gl->InsertFenceSyncCHROMIUM();
 
     gl->Flush();
-    GLbyte syncToken[24];
+    GLbyte syncToken[GL_SYNC_TOKEN_SIZE_CHROMIUM] = { 0 };
     gl->GenSyncTokenCHROMIUM(fenceSync, syncToken);
     m_gl->WaitSyncTokenCHROMIUM(syncToken);