Fix the crash of compressedTexImage3D for the WebGL2 conformance test page.

third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp

Index: third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
diff --git a/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp b/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
index e8d9ee846d1ac3f0b0e95e7e5915a68a22b34ce5..6d17a01fbb92734f2384a07b9bde64db73b7b3c0 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
+++ b/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
@@ -929,6 +929,9 @@ void WebGL2RenderingContextBase::compressedTexImage3D(GLenum target, GLint level
     if (!tex)
         return;
 
+    if (!validateTexFuncLevel("compressedTexImage3D", target, level))

[zmo, 2015/11/23 19:07:14]

I agree with Qiankun this is the right thing to do.  However, you need to update
getMaxTextureLevelForTarget() to handle 3D texture targets to make it work.

+        return;
+
     if (tex->isImmutable()) {
         synthesizeGLError(GL_INVALID_OPERATION, "compressedTexImage3D", "attempted to modify immutable texture");
         return;