logic: added Gradle project setup (issue #379)

* added implementation for Gradle project setup (icon is still missing)
* refactored project loading/saving and SourceGroupSettings
* removed long deprecated Cxx UseSourcePathsForHeaderSearch option

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src/lib_cxx/project/SourceGroupCxxEmpty.cpp

@@ -0,0 +1,106 @@
+#include "project/SourceGroupCxxEmpty.h"
+
+#include "data/indexer/IndexerCommandCxxManual.h"
+#include "settings/ApplicationSettings.h"
+#include "utility/utility.h"
+#include "Application.h"
+
+SourceGroupCxxEmpty::SourceGroupCxxEmpty(std::shared_ptr<SourceGroupSettingsCxxEmpty> settings)
+	: m_settings(settings)
+{
+}
+
+SourceGroupCxxEmpty::~SourceGroupCxxEmpty()
+{
+}
+
+SourceGroupType SourceGroupCxxEmpty::getType() const
+{
+	return m_settings->getType(); // may be either C or Cpp
+}
+
+std::vector<std::shared_ptr<IndexerCommand>> SourceGroupCxxEmpty::getIndexerCommands(
+	std::set<FilePath>* filesToIndex, bool fullRefresh)
+{
+	std::shared_ptr<ApplicationSettings> appSettings = ApplicationSettings::getInstance();
+
+	std::vector<FilePath> systemHeaderSearchPaths;
+	utility::append(systemHeaderSearchPaths, m_settings->getHeaderSearchPathsExpandedAndAbsolute());
+	utility::append(systemHeaderSearchPaths, appSettings->getHeaderSearchPathsExpanded());
+
+	// Add the source paths as HeaderSearchPaths as well, so clang will also look here when searching include files.
+	for (const FilePath& sourcePath: m_settings->getSourcePathsExpandedAndAbsolute())
+	{
+		if (sourcePath.isDirectory())
+		{
+			systemHeaderSearchPaths.push_back(sourcePath);
+		}
+	}
+
+	std::vector<FilePath> frameworkSearchPaths;
+	utility::append(frameworkSearchPaths, m_settings->getFrameworkSearchPathsExpandedAndAbsolute());
+	utility::append(frameworkSearchPaths, appSettings->getFrameworkSearchPathsExpanded());
+
+	std::vector<std::string> compilerFlags;
+	{
+		const std::string targetFlag = m_settings->getTargetFlag();
+		if (!targetFlag.empty())
+		{
+			compilerFlags.push_back(targetFlag);
+		}
+	}
+
+	utility::append(compilerFlags, m_settings->getCompilerFlags());
+
+	std::set<FilePath> indexedPaths;
+	for (const FilePath& p : m_settings->getSourcePathsExpandedAndAbsolute())
+	{
+		if (p.exists())
+		{
+			indexedPaths.insert(p);
+		}
+	}
+
+	std::set<FilePath> excludedPaths;
+	for (const FilePath& p: m_settings->getExcludePathsExpandedAndAbsolute())
+	{
+		if (p.exists())
+		{
+			excludedPaths.insert(p);
+		}
+	}
+
+	const std::set<FilePath>& sourceFilePathsToIndex = (fullRefresh ? getAllSourceFilePaths() : getSourceFilePathsToIndex());
+
+	std::vector<std::shared_ptr<IndexerCommand>> indexerCommands;
+	for (const FilePath& sourcePath: sourceFilePathsToIndex)
+	{
+		if (filesToIndex->find(sourcePath) != filesToIndex->end())
+		{
+			indexerCommands.push_back(std::make_shared<IndexerCommandCxxManual>(
+				sourcePath,
+				indexedPaths,
+				excludedPaths,
+				m_settings->getStandard(),
+				systemHeaderSearchPaths,
+				frameworkSearchPaths,
+				compilerFlags,
+				m_settings->getShouldApplyAnonymousTypedefTransformation()
+			));
+
+			filesToIndex->erase(sourcePath);
+		}
+	}
+
+	return indexerCommands;
+}
+
+std::shared_ptr<SourceGroupSettingsCxx> SourceGroupCxxEmpty::getSourceGroupSettingsCxx()
+{
+	return m_settings;
+}
+
+std::vector<FilePath> SourceGroupCxxEmpty::getAllSourcePaths() const
+{
+	return m_settings->getSourcePathsExpandedAndAbsolute();
+}