Merge pull request #21083 from OrestChura:oc/fix_coverity_vino_issues

[G-API] Fixed Coverity issues

* Fixed Coverity issues
 - VectorRef&OpaqueRef m_kind = CV_UNKNOWN
 - added same-type overload for saturate()
 - sanitized resize value in ByteMemoryInStream::operator>> (std::string& str)
 - handled throws from ~GStreamingExecutor()

* Catching exception by const ref

* Addressing Sergey's comments

* Applied enable_if semanitcs to saturate(x, round) too

* Removed uncaught_exception, made destructor noexcept back

* Split Fluid ConvertTo to multiple functions to avoid ifs; added CV_ALWAYS_INLINE

* Added FIXME to address throwings from stop()

* Fix standalone

* Addressing comments

* Guarded SIMD optimizations properly

* Removed excess parameter from simd_impl functions

modules/gapi/src/executor/gstreamingexecutor.cpp

@@ -24,6 +24,8 @@
 #include "backends/streaming/gstreamingbackend.hpp" // GCopy
 #include "compiler/gcompiler.hpp" // for compileIslands
 
+#include <logger.hpp>
+
 #include "executor/gstreamingexecutor.hpp"
 
 #include <opencv2/gapi/streaming/meta.hpp>
@@ -1382,8 +1384,16 @@ cv::gimpl::GStreamingExecutor::GStreamingExecutor(std::unique_ptr<ade::Graph> &&
 
 cv::gimpl::GStreamingExecutor::~GStreamingExecutor()
 {
-    if (state == State::READY || state == State::RUNNING)
-        stop();
+    // FIXME: this is a temporary try-catch exception hadling.
+    // Need to eliminate throwings from stop()
+    try {
+        if (state == State::READY || state == State::RUNNING)
+            stop();
+    } catch (const std::exception& e) {
+        std::stringstream message;
+        message << "~GStreamingExecutor() threw exception with message '" << e.what() << "'\n";
+        GAPI_LOG_WARNING(NULL, message.str());
+    }
 }
 
 void cv::gimpl::GStreamingExecutor::setSource(GRunArgs &&ins)