Bug 323489 [KeyBindings] Reduce memory footprint of BindingManager
bundles/org.eclipse.jface/src/org/eclipse/jface/bindings/BindingManager.java
if (existingCache == null) {
			existingCache = bindingCache;
			cachedBindings.put(existingCache, existingCache);
		}
		Map triggersByParameterizedCommand = existingCache
				.getTriggersByCommandId();
		if (triggersByParameterizedCommand != null) {
			if (DEBUG) {
				Tracing.printTrace("BINDINGS", "Cache hit"); 
			}
			return Collections.unmodifiableMap(triggersByParameterizedCommand);
		}
		
		if (DEBUG) {
			Tracing.printTrace("BINDINGS", "Cache miss"); 
		}
		
		final Map commandIdsByTrigger = new HashMap();
		final Map conflictsByTrigger = new HashMap();
		triggersByParameterizedCommand = new HashMap();
		computeBindings(null, commandIdsByTrigger,
				triggersByParameterizedCommand, conflictsByTrigger);
		existingCache.setBindingsByTrigger(commandIdsByTrigger);
		existingCache.setTriggersByCommandId(triggersByParameterizedCommand);
		existingCache.setConflictsByTrigger(conflictsByTrigger);
		return Collections.unmodifiableMap(triggersByParameterizedCommand);
	}
	/**
	 * <p>
	 * Computes the bindings for the current state of the application, but