Disable pre-compilation of OpenCL kernels for now.

Change-Id: I1e61fab8ae26c11af05084db1a5542c066f69852

sc/source/core/data/formulacell.cxx

@@ -54,7 +54,7 @@
 
 #include <boost/scoped_ptr.hpp>
 
-#define ENABLE_THREADED_OPENCL_KERNEL_COMPILATION 1
+#define ENABLE_THREADED_OPENCL_KERNEL_COMPILATION 0
 
 using namespace formula;
 
@@ -3506,8 +3506,6 @@ ScFormulaCellGroupRef ScFormulaCell::CreateCellGroup( SCROW nLen, bool bInvarian
 #if ENABLE_THREADED_OPENCL_KERNEL_COMPILATION
     if (mxGroup->sxCompilationThread.is())
         mxGroup->scheduleCompilation();
-#else
-    mxGroup->compileOpenCLKernel();
 #endif
     return mxGroup;
 }

sc/source/core/opencl/formulagroupcl.cxx

@@ -3208,6 +3208,10 @@ DynamicKernel::~DynamicKernel()
 /// Build code
 void DynamicKernel::CreateKernel(void)
 {
+    if (mpKernel)
+        // already created.
+        return;
+
     cl_int err;
     std::string kname = "DynamicKernel"+mKernelSignature;
     // Compile kernel here!!!