Sharing links can't be used to generate further sharing links

## I'm submitting a ...
Check one of the following options with "x" and add the appropriate label to the issue as well

[X] Bug report 

[ ] Regression (behaviour that used to work and stopped working in a new release)

**Describe the Issue**
When user accesses the Hub via a Hub-Generated link, then configures an indicator within global picture, then shares this via the chart button (as configured), a broken link is generated.

**To Reproduce**
Replace the content below with the steps to reproduce the behaviour.
1. Go to 'http://data.devinit.org/global-picture/'
2. Click on 'share this chart'
3. Copy link
4. Follow link
5. Click on 'Share this chart'
6. Copy link
7. Follow link
8. See error

**Expected Behaviour**
The correct behaviour would see the button producing a link based on the chart settings rather than the present URL, since the present URL will not always be what is required.

**Screenshots/GIF**
If applicable, add screenshots or a GIF to help explain your problem.

**Desktop (please complete the following information):**
- OS: [Windows 7]
- Browser [Chrome]
- Version [69.0.3497.100]

**Smartphone (please complete the following information):**
- Device: [e.g. iPhone6]
- OS: [e.g. iOS8.1]
- Browser [e.g. stock browser, safari]
- Version [e.g. 22]

**Environment/Server:**

- [ ] Production

- [ ] Staging

- [ ] Test

- [ ] Development

**Additional Context**
Add any other context about the problem here.

Requested Delivery Date: dd/MMM/YYYY