Eliminate TooManySeeks exception (#611)

Since commit bfa0504 (2015-08-24),
there is no code in libopenshot which ever throws TooManySeeks.

- Removed catch() statements for TooManySeeks from multiple functions
- Removed the exception from Exceptions.h
- in Qt/AudioPlaybackThread.h:
  - Removed the "SafeTimeSliceThread" class definition, as it only
    existed to catch TooManySeeks.
  - Replaced SafeTimeSliceThread with a standard juce::TimeSliceThread

Author: ferdnyc

src/AudioReaderSource.cpp

@@ -97,8 +97,6 @@ void AudioReaderSource::GetMoreSamplesFromReader()
 
 			} catch (const ReaderClosed & e) {
 			break;
-			} catch (const TooManySeeks & e) {
-			break;
 			} catch (const OutOfBoundsFrame & e) {
 			break;
 			}

src/Clip.cpp

@@ -717,8 +717,6 @@ std::shared_ptr<Frame> Clip::GetOrCreateFrame(int64_t number)
 
 	} catch (const ReaderClosed & e) {
 		// ...
-	} catch (const TooManySeeks & e) {
-		// ...
 	} catch (const OutOfBoundsFrame & e) {
 		// ...
 	}

src/Exceptions.h

@@ -365,22 +365,6 @@ namespace openshot {
 		virtual ~ResampleError() noexcept {}
 	};
 
-	/// Exception when too many seek attempts happen
-	class TooManySeeks : public ExceptionBase
-	{
-	public:
-		std::string file_path;
-		/**
-		 * @brief Constructor
-		 *
-		 * @param message A message to accompany the exception
-		 * @param file_path (optional) The input file being processed
-		 */
-		TooManySeeks(std::string message, std::string file_path="")
-			: ExceptionBase(message), file_path(file_path) { }
-		virtual ~TooManySeeks() noexcept {}
-	};
-
 	/// Exception when a writer is closed, and a frame is requested
 	class WriterClosed : public ExceptionBase
 	{

src/FrameMapper.cpp

@@ -369,8 +369,6 @@ std::shared_ptr<Frame> FrameMapper::GetOrCreateFrame(int64_t number)
 
 	} catch (const ReaderClosed & e) {
 		// ...
-	} catch (const TooManySeeks & e) {
-		// ...
 	} catch (const OutOfBoundsFrame & e) {
 		// ...
 	}

src/Qt/AudioPlaybackThread.h

@@ -40,18 +40,6 @@
 
 namespace openshot
 {
-	struct SafeTimeSliceThread : juce::TimeSliceThread
-	{
-		SafeTimeSliceThread(const String & s) : juce::TimeSliceThread(s) {}
-		void run()
-		{
-			try {
-				juce::TimeSliceThread::run();
-			} catch (const TooManySeeks & e) {
-				// ...
-			}
-		}
-	};
 
 	/**
 	 *  @brief Singleton wrapper for AudioDeviceManager (to prevent multiple instances).
@@ -96,8 +84,7 @@ namespace openshot
 		juce::WaitableEvent played;
 		int buffer_size;
 		bool is_playing;
-		SafeTimeSliceThread time_thread;
-
+		juce::TimeSliceThread time_thread;
 		/// Constructor
 		AudioPlaybackThread();
 		/// Destructor

src/Qt/PlayerPrivate.cpp

@@ -174,8 +174,6 @@ namespace openshot
 
     } catch (const ReaderClosed & e) {
         // ...
-    } catch (const TooManySeeks & e) {
-        // ...
     } catch (const OutOfBoundsFrame & e) {
         // ...
     }

src/Timeline.cpp

@@ -461,8 +461,6 @@ std::shared_ptr<Frame> Timeline::GetOrCreateFrame(Clip* clip, int64_t number)
 
 	} catch (const ReaderClosed & e) {
 		// ...
-	} catch (const TooManySeeks & e) {
-		// ...
 	} catch (const OutOfBoundsFrame & e) {
 		// ...
 	}