Merge ~j.kylmala/cloud-init:exceptions into cloud-init:master

[Joonas Kylmälä]

tools: Fix exception handling.

We should be expecting IndexError instead of KeyError because we are
using a list (key_ids) and not a dictionary. Also, thanks to Emmanuel
Kasper for pointing out the wrong response code.

LP: #1701527

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:ec81bec2285a498c2c754572755929d983db3ef8
https://jenkins.ubuntu.com/server/job/cloud-init-ci/36/
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diff --git a/tools/mock-meta.py b/tools/mock-meta.py
index f185dbf..a5d14ab 100755
--- a/tools/mock-meta.py
+++ b/tools/mock-meta.py
@@ -262,8 +262,8 @@ class MetaDataHandler(object):
                 except ValueError:
                     raise WebException(hclient.BAD_REQUEST,
                                        "%s: not an integer" % mybe_key)
-                except KeyError:
-                    raise WebException(hclient.BAD_REQUEST,
+                except IndexError:
+                    raise WebException(hclient.NOT_FOUND,
                                        "Unknown key id %r" % mybe_key)
                 # Extract the possible sub-params
                 result = traverse(nparams[1:], {